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307 Cards in this Set
- Front
- Back
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Scientific Method
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A method of procedure that scientists use when conducting an experiment.
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Parts of the Scientific Method
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Observation, Research, Hypothesis, Experiment, Data collection, analysis, Conclusion, Communication.
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Independent variable
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The variable scientists change in the experiment.
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Dependent Variable
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The variable scientists observe or measure to see if it is affected by a change in the independent variable.
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Controlled Experiment
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An experiment in which all variables except one are held constant.
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Control Group
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The group in an experiment or study that has no variables changed by the researchers.
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Experimental Group
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The group in which a variable is changed in an experiment.
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Constants
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Variables that should not change during an experiment.
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Theory
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An explanation of an event or phenomenon that is well supported by data.
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Law
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A description of a natural event or phenomenon shown to occur again and again under the same conditions.
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Accuracy
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How close a measured value is to the true measurement (true value) of something.
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Precision
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The ability to take the same measurement and get the same result over and over.
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Mass
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A measure of the quantity (or amount) of material in a substance.
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Weight
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A measure of the pull of gravity between an object and the earth (or the planets, sun, etc.).
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Length
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A measure of how long an object is or the distance an object spans.
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Volume
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The amount of space that matter occupies or takes up.
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Temperature
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A measure of the average kinetic energy (energy of motion) of particles of matter.
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Density
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The amount of matter per unit of volume.
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Pressure
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The amount of force exerted per unit area.
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Energy
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A measure of the ability to do work or generate heat.
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Kilogram
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SI unit of mass.
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Meter
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SI unit of length.
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Liter/Cubic Centimeter
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SI unit of volume.
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Degrees Celsius
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SI unit of temperature.
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Grams per Cubic Centimeter/Grams per Milliliter
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SI unit of density.
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Joule
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SI unit of energy.
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Pascal
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SI unit of pressure.
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Extrinsic Property
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Property that changes based on the amount of substance present.
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Intrinsic Property
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Property that does not change based on the amount of substance present.
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Tera
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Prefix for one trillion.
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Giga
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Prefix for one billion.
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Mega
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Prefix for one million.
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Kilo
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Prefix for one thousand.
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Hecto
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Prefix for one hundred.
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Deca
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Prefix for ten.
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Deci
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Prefix for one–tenth.
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Centi
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Prefix for one–hundredth.
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Milli
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Prefix for one–thousandth.
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Micro
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Prefix for one–millionth.
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Nano
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Prefix for one–billionth.
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Pico
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Prefix for one–trillionth.
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Scientific Notation
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A way of expressing numbers that are too big or too small to be conveniently written in decimal form.
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1.24032 × 10^11
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124,032,000,000 =
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9.7463 × 10^–6
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0.0000097463 =
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Pure Substance
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A uniform substance made up of one type of particle.
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Mixture
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Two or more substances that are combined physically but not chemically.
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Element
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A pure substance that cannot be broken down by normal chemical or physical means.
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Allotropes
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Different forms of the same element in the same physical state of matter.
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Compound
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A pure substance made up of two or more elements joined in a defined ratio.
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Homogeneous
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A type of mixture that appears uniform throughout.
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Solution
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A homogeneous mixture in which one or more substances (solutes) are dissolved in another substance (solvent).
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Solute
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The substance that is dissolved in the solution.
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Solvent
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The substance that the solute is dissolved in in a solution.
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Soluble
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Able to be dissolved, especially in water.
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Heterogenous
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A mixture in which the components are not mixed evenly or uniformly distributed throughout.
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Colloid
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Mixture of fine particles.
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Sol
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Solid in liquid or solid.
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Gel
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Liquid in solid.
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Foam
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Gases finely spread through liquid or solid.
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Aerosol
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Colloidal suspension of liquid or fine solid in gas.
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Emulsion
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Liquid in liquid.
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Physical
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A property of matter that can be observed without changing the substance into another substance.
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Chemical
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Property determined by the ability of a substance to react with or change into another substance.
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Solid
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Substance with a definite volume and a definite shape.
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Liquid
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Substance without a definite volume and with a definite shape.
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Gas
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Substance without a definite volume or shape.
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Effusion
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The movement of gas particles through a small hole in a container from an area of high pressure to an area of low pressure.
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Diffusion
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The movement of particles from an area of high concentration to an area of low concentration.
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Molecular Mass
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The mass of one molecule of a substance.
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Plasma
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An ionized gas.
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Surface Tension
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A property of liquids that describes the attraction of liquid molecules at the surface.
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Viscosity
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A measure of a liquid's resistance to flow.
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Crystalline
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This solid is made up of atoms or molecules that are organized in specific repeating patterns. These regular, repeating patterns form crystals.
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Amorphous
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A solid made up of atoms or molecules that do not organize into a specific form or a neat, repeating structure.
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Physical
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Any change in a substance’s form that does not change its chemical makeup.
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Phase Change
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A change from one state to another.
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Melting
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Solid to Liquid.
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Freezing
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Liquid to Solid.
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Vaporization
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Liquid to Gas.
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Condensation
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Gas to Liquid.
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Sublimation
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Solid to Gas.
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Deposition
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Gas to Solid.
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Dew point
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The temperature at which a gas begins to condense into a liquid.
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Phase changes occur because a substance has been given energy or because energy has been taken away.
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Why do phase changes occur?
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Chemical Change
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A change that takes place when atoms of a/some substance(s) are rearranged.
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Energy
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The ability to do work or produce heat.
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Law of conservation of energy
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Energy can change from one form to another, but it cannot be created or destroyed.
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Kinetic Energy
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Energy of Motion.
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Formula for Kinetic Energy
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1/2 × mv^2.
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Potential Energy
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Stored energy.
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Formula for Potential Energy
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mgh.
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Mechanical Energy
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Energy determined by the motion or position of an object.
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Exothermic Change
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A change that releases energy.
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Endothermic change
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A change that absorbs energy.
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Separation Process
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A process that divides a mixture into two or more different parts.
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Filtration
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A way of separating a mixture based on differences in size between the particles that make up different parts of the mixture.
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Precipitation
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A means of separating a component in a solution by reacting it with another substance to form a solid.
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Atom
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The smallest constituent unit of ordinary matter that has the properties of a chemical element.
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Proton
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A subatomic particle with symbol p or p+ with a +1 charge.
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Neutron
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A neutral particle with symbol n or n0 with a 0 charge.
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Nucleus
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The tiny, dense core of an atom, with nearly all its mass.
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Electron
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A tiny particle symbolized e or e–, with a –1 charge.
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Quark
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A small particle that makes up protons and neutrons with a charge of either +2/3 or –1/3.
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Types of Quark
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Up, Down, Charm, Strange, Top, Bottom.
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Molecule
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A neutral particle composed of two or more atoms held together by chemical bonds.
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Atomic Number
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The number of protons in an atom’s nucleus.
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Mass Number
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The number of protons plus the number of neutrons in an atom’s nucleus.
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Chemical symbol
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An abbreviation or short representation of a chemical element.
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Ion
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An atom that has gained or lost an electron.
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Anion
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A negatively charged ion.
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Cation
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A positively charged ion.
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Ionization
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The process of becoming an ion (gaining or losing an electron).
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Isotopes
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Atoms of the same element with different numbers of neutrons.
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Atomic Weight
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The “weighted” average mass of all of an element’s isotopes.
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Periodic Table
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A table of the chemical elements arranged in order of atomic number.
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Group
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A vertical column of the periodic table.
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Period
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A horizontal row of the periodic table.
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Metal
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A solid material that is typically hard, shiny, malleable, fusible, and ductile, with good electrical and thermal conductivity.
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Nonmetal
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A material (usually a gas) that typically has poor electrical and thermal conductivity and a lower melting point than metals (except for carbon).
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Metalloid
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A material with properties between metals and nonmetals.
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Alkali Metal
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A metal in group IA.
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Alkali Earth Metal
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A metal in group IIA.
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Transition Metal
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A metal in groups IIIA – IIB.
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Halogen
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A nonmetal in group VIIA.
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Noble Gas
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A nonmetal in group VIIIA.
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Inner transition metals
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Consists of Lanthanides and Actinides and are not part of any group.
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Lanthanide series
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Inner transition metals of period 6.
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Actinide Series
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Inner transition metal of period 7.
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Electron Configuration
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The term for how electrons are arranged in an atom.
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Heisenberg’s Uncertainty Principle
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States that it is impossible to measure two properties of a quantum object, such as its position and momentum (or energy and time), simultaneously with infinite precision.
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Orbital
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An area that an electron is likely to be in.
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Principal Quantum Number
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A whole number (1, 2, 3 …) that gives us an idea of the size of the orbital.
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Subshell
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A subdivision of electron shells separated by electron orbitals.
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Beaker
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A wide, open container with a flat bottom made of glass or plastic.
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Flask
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A glass container with a thin “neck” that widens to a rounded base. Flasks can be used to measure, heat, or store liquids.
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Erlenmeyer flask
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A flask with a cone–shaped base.
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Florence flask
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A round flask that may have a rounded or flatbottomed base.
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Volumetric Flask
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A flask with a pear–shaped base and a long neck that can hold a certain volume, marked by a black line.
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Test tube
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A small cylindrical glass tube that has a rounded, U–shaped bottom.
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Buret
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A long glass cylinder used to accurately measure and dispense a specific volume of liquid.
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Graduated cylinder
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A tall, cylindrical container used to measure the volume of a liquid.
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Triple–beam balance
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A device used to measure the mass of an object by comparing the objects’ mass to the mass of predetermined “weights” known as riders.
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Analytical Balance
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Measures masses with its pan with great accuracy.
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Thermometer
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A device used to measure temperature.
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Manometer
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A device used to measure the pressure of a fluid.
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Barometer
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A type of manometer used to measure atmospheric pressure.
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Pipette
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A device used to measure and move a liquid from one container to another.
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Bunsen burner
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A flame for laboratory experiments. The flame burns at the top of a vertical metal tube connected to a natural gas source.
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Safety data sheet
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This gives workers, emergency personnel, and all of us informationabout the proper way to handle or work with a certain substance.
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Lewis Symbol (Electron Dot Structure) |
A structure with dots to symbolize valence electrons. |
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Valence Electron |
An electron in the highest energy level of an atom. |
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Core Electron |
An electron that is not a valence electron and does not usually participate in chemical reactions. |
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Octet Rule |
A chemical rule of thumb that states that main group atoms tend to gain, lose, or share electrons to achieve eight valence electrons. |
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Chemical Formula |
A set of chemical symbols showing the elements present in a compound and their relative proportions. |
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Oxidation Number |
A number assigned to an element in a compound that represents the number of electrons lost by an atom of that element in the compound. |
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Ethanol(C2H5OH) |
Grain Alcohol |
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Sodium hypochlorite (NaOCl) |
Bleach |
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Trichloromethane (CHCl3) |
Chloroform |
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Nitrous oxide (N2O) |
Laughing Gas |
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Sodium hydroxide (NaOH) |
Lye |
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Calcium oxide (CaO) |
Quicklime |
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Silicon dioxide (SiO2) |
Sand (silica) |
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Sodium chloride (NaCl) |
Table Salt |
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Sucrose (C12H22O11) |
Cane Sugar |
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Acetic acid (CH3COOH) |
Vinegar |
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Water |
H20 |
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Methanol (CH3OH) |
Wood Alchohol |
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Chemical nomenclature |
The system used for naming chemical substances. |
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Monatomic ion |
An ion made up of only one element. |
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Polyatomic ion |
An ion made up of more than one element. |
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The Element's Group Number |
Valence electrons for elements in groups 1-2. |
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The Element's Group Number Minus Ten |
Valence electrons for elements in groups 13-18. |
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Full Octet |
A full group of eight valence electrons. |
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Full Octet |
Valence electrons for elements in Group 18. |
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Subscripts |
These indicate how many atoms of each element are in a compound. |
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The least electronegative element in the compound |
What element comes first in a chemical formula? |
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How to determine oxidation numbers |
Oxidation numbers are determined by how many electrons an element needs to gain to recieve a full octet. |
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Aqueous Solution |
A solution in which the solvent is water. |
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How to name a monatomic cation |
Use the element's name. If there is more than one cation, show positive charge in roman numerals after the element. |
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How to name a monatomic anion |
Use the element's name but replace the ending with "-ide". |
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-ium |
What do polyatomic cations' names end in? |
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-ite or -ate |
What do the names of oxyanions end in? |
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-ate has one more oxygen than -ite |
What is the difference between oxyanions with -ite and -ate? |
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Start with the name of the cation, and then add the name of the anion. |
How do you name ionic compounds? |
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Binary Acid |
An acid with hydrogen and one other element that does not contain oxygen. |
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How to name binary acids |
Start with the prefix "hydro-" and add the name of the anion. Then, change the ending from "-ide" to "-ic" and add "acid" to the name. |
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Oxyacid |
An acid containing oxygen. |
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Take the anion, and change the "-ate" to "-ic acid". |
How do you name "-ate" oxyacids? |
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Take the anion, and change the "-ite" to "-ous acid". |
How do you name "-ite" oxyacids? |
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mono- |
Prefix for one |
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di- |
Prefix for two |
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tri- |
Prefix for three |
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tetra- |
Prefix for four |
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penta- |
Prefix for five |
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hexa- |
Prefix for six |
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hepta- |
Prefix for seven |
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octa- |
Prefix for eight |
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nona- |
Prefix for nine |
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deca- |
Prefix for ten |
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How to name binary molecular compounds |
Write the name of the least electronegative element, then the other element's name, then use greek prefixes to represent the number of atoms of each element of a compound. |
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Intermolecular force |
A force that acts within a molecule. |
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Intramolecular force |
A force that acts between molecules. |
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Coulomb's Law |
This law states that opposite charges attract, and similar charges push each other away. |
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Electronegativity |
A chemical property that describes how strongly the nucleus of an atom attracts the electronsin a chemical bond. |
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Increase |
Electronegativity tends to _______ from left to right within a period. |
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Decrease |
Electronegativity tends to ________ from top to bottom within a group. |
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Ionization Energy |
The amount of energy needed to remove one of the outermost electrons from a neutral atom in the gas phase. |
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Increase |
Ionization energy tends to ________ from left to right across the periodic table within a period. |
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Decrease |
Ionization energy tends to ________ from top to bottom down the periodic table within a group. |
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Atomic Radius |
The typical distance from the nucleus of an atom to the boundary of its electron cloud. |
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Decrease |
Atomic radius tends to ________ from left to right across the periodic table. |
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Increase |
Atomic radius tends to ________ from top to bottom down theperiodic table. |
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Chemical Bond |
An intramolecular force of attraction that holds together atoms in a molecule orcompound. |
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Ionic bonds |
These bonds occur when one atom gives up electrons and another atom takes them. |
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Ionic compounds |
Compounds held together by ionic bonds |
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Covalent bonds |
These bonds occur when valence electrons are shared between two nonmetal atoms, which have similar electronegativities and are close to one another on the periodic table. |
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Single covalent bond (single bond) |
A covalent bond sharing only one pair of electrons (two electrons total) between two atoms. |
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Double covalent bond (double bond) |
A covalent bond sharing two pairs of electrons (four electrons total) between two atoms. |
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Triple covalent bond (triple bond) |
A covalent bond sharing three pairs of electrons (six electrons total) between two atoms. |
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Metallic bonding |
These bonds occur when metal atoms bond by contributing their electrons to a “sea” of shared electrons. |
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Luster |
The ability to reflect light |
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Electrical conductivity |
A measure of the rate at which electricity can travel through a material. |
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Thermal conductivity |
A measure of the rate at which thermal energy can travel through a material. |
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Malleability |
The ability of a metal to be flattened, shaped, or formed without breaking when pressure is applied. This includes the ability of a metal to be hammered into a thin sheet. |
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Ductility |
The ability of a metal to be stretched into a thin wire or thread without breaking. |
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Chemical reaction |
This occurs when the atoms of one or more substances are rearranged to produce one or more different substances.
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Reactants |
The starting material or materials for a chemical reaction. |
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Products |
The substance or substances produced from a chemical reaction. Sometimes one or more of the products can be classified as byproducts. |
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Reactants --> Products |
How a chemical reaction is generally represented. |
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Reaction pathway |
The road that atoms and molecules take to get from starting materials to products. |
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Reaction coordinate diagram |
This plots the energy of the reaction versus how far the reaction has progressed. |
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Activation energy |
The minimum amount of energy needed to start a chemical reaction. |
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Collision theory |
This explains that gas-phase chemical reactions occur when molecules collide with sufficient kinetic energy. |
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Radioactivity |
The spontaneous breakdown of an unstable nucleus in an atom |
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Radioisotopes |
Atoms that are radioactive. |
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Half-Life |
The time it takes for one-half of the nuclei present in a sample to undergo radioactive decay. |
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Alpha Particle |
Helium-4 nucleus |
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Beta Particle |
Electron |
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Gamma Particle |
High-energy photon |
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Nuclear Reactions |
Changes that occur in the structure of atomic nuclei. |
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Nuclear Fission |
A nuclear reaction that occurs when an atomic nucleus splits into two smaller parts. |
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Nuclear Fusion |
A nuclear reaction that occurs when thenuclei of two atoms join to make a larger nucleus. |
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Transuranic Element |
Element with atomic number greater than 92 |
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Acids |
Substances that release hydrogen ions (H+) when dissolved in water. |
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Bases |
Substances that either release hydroxide ions (OH-) when dissolved in water or that accept H+ ions from acids. |
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Alkalis |
A type of base made of ionic salts of an alkali metal or an alkaline earth metal. |
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Down |
Within a group, acid strength increases as atomic radiusincreases moving ____ the periodic table. |
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pH scale |
Used to measure the acidity of a solution. |
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100 |
The pH scale is logarithmic. Therefore, pH 5 acid is ___ times weaker than pH 3 acid? |
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1,000 |
The pH scale is logarithmic. Therefore, pH 10 base is ___ times weaker than pH 13 base? |
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Right |
Within a period, acid strength increases as electronegativity increases moving _____ across the periodic table. |
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Litmus paper |
Indicator that changes red in an acidic solution and blue in a basic solution. |
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Phenolphthalein solution |
Indicator that changes from colorless to pink for a pH greater than 8.2. |
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Bromothymol Blue |
This turns yellow in acidic solutions and blue in basic solutions. |
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Chemical Equation |
The symbolic representation of a chemical reaction in the form of symbols and formulae. |
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Law of conservation of mass |
Matter cannot be created or destroyed, although it may be changed. |
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Equal |
The number of atoms of each element on the reactants side _____ the number of atoms of each element on the products side. |
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Chemical Kinetics |
The field of science that studies the rates of chemical reactions. |
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Catalyst |
A substance that changes the rate of a reaction. |
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Temperature and Concentration |
How can the rate of a chemical reaction be increased? |
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Exothermic reactions |
Chemical reactions that produce energy. |
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Endothermic reactions |
Chemical reactions that require the input of energy to occur. |
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Synthesis reaction |
A chemical reaction in which smaller molecules combine to form a larger one. |
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Decomposition Reaction |
A chemical reaction in which a compound breaks apart into two or more products. |
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Single Displacement Reaction |
A chemical reaction in which a reactant takes the place of some part of a compound. |
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Double Displacement Reaction |
A chemical reaction between two compounds in which part of one reactant trades places with part of another reactant. |
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Oxidation-Reduction (redox) Reaction |
A chemical reaction in which at least one atom’s oxidation number changes. |
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Oxidation |
A chemical reaction that involves an increase in oxidation number. |
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Reduction |
A chemical reaction that involves a decrease in oxidation number. |
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Combustion |
A redox reaction with oxygen as a reactant that occurs rapidly and produces energy, usually in the form of heat and light. |
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Corrosion |
A redox reaction that occurs when a metal is oxidized, usually in the presence of moist air. The rusting of iron is a corrosion process. |
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Reversible reactions |
Reactions that can go forward (from reactants to products) or backward. |
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Equilibrium |
The state of a chemical reaction in which the forward and reverse reactions occur at the same rate. |
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Covalent compounds |
Compounds made up of one or more nonmetal atoms connected by covalent bonds. |
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Lines |
In the Lewis structure of a covalent compound, _____ are used to represent the sharing of electrons (covalent bonds). |
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Gravity |
A force which tries to pull any two objects toward each other. |
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Magnet |
An object that creates a strong magnetic field (area of magnetic force). |
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Magnetism |
A physical phenomenon produced by the motion of electric charge, resulting in attractive and repulsive forces between objects. |
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Permanent Magnet |
This keeps a certain level of magnetism for a long time. |
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Temporary Magnet |
This acts like a permanent magnet when it is within a strong magnetic field. |
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Chemical Reaction |
A process that involves rearrangement of the molecular or ionic structure of a substance. |
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Reactant(s) |
The starting material or materials for a chemical reaction. |
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Product(s) |
The substance or substances produced by a chemical reaction. |
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Reactants --> Products |
In general, a chemical reaction is represented in this way. |
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Reaction Pathway |
The road that atoms and molecules take to get fromstarting materials to products. |
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Reaction Coordinate Diagram |
Graphs the energy of the reaction versus how far the reaction has progressed. |
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∆E |
This represents the overall change in energy during a reaction. |
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Activation energy |
The minimum amount of energy needed to starta chemical reaction. |
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Transition state |
A state where thebonds in the reactants are in the process of breaking and the bonds inthe products are in the process of forming. Highest point in reaction coordinate diagram. |
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Chemical kinetics |
The field of science that studies the rates of chemical reactions. |
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Requirements for a chemical reaction |
Particles of the reactants must collide with each another, have enough energy to react (activation energy), and have the proper orientation to react. |
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Collision theory |
Particles sometimes they will collide with one another through random motion. If theycollide with enough energy and the right orientation, they react. The frequency of particles colliding with each othersuccessfully and reacting determines the reaction rate. |
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Ways to increase the rate of a chemical reaction |
Concentration, Temperature, Catalysts |
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Catalyst |
A substance that lowers reaction activation energy while not being changed by the reaction itself. |
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Enzyme |
A biological catalyst |
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Exothermic reactions |
Chemical reactions that produce energy, often inthe form of heat, light, or sound. ∆E is negative. |
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Endothermic reactions |
Chemical reactions that require the input of energy to occur. ∆E is positive. |
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Chain Reaction |
A series of chemical reactions in which the products of one reaction initiate furtherreactions of the same kind until a stable product is formed. |
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Increases |
Within a group, acid strength ________ as atomic radius increases moving down the periodic table. |
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Radioactivity |
The spontaneous breakdown of an unstable nucleus in an atom |
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Radioisotopes |
Atoms that are radioactive. |
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Half-life |
The time it takes for one-half of the nuclei present in a sample to undergo radioactive decay. |
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Alpha particle |
Radiationcomposed of helium-4 nuclei. |
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Eight |
Main group elements have up to _____ valence electrons. |
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Formula unit |
One molecule of an element, or the lowest whole number ratio of ions represented in an ionic compound. |
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Transferring electrons (giving, taking, sharing) |
Atoms with less than eight valence electrons form bonds by... |
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Period (of element) |
Energy level of the valence electron relates to... |
