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70 Cards in this Set
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Science |
Science is a way of organising and explaining the knowledge about ourselves and our surroundings. |
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Scientific disciplines |
Scientific disciplines are branches of science which limit the amount of knowledge to make scientific study more manageable. |
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There are 2 fundamental properties in the universe, what are they? |
Energy and matter. The study of these 2 properties is central to understanding all science. |
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We are all made of elements called what? |
Atoms |
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What is the scientific discipline which deals with matter |
Chemistry |
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Historically, the discipline of chemistry was divided into 2 major areas. What were they? |
Organic chemistry and inorganic chemistry |
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Organic chemistry |
The study of carbon and its compounds, the term organic comes from the Greek word meaning living matter. |
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Inorganic chemistry |
The study of all other elements, in organic means inanimate or non living. |
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Besides chemistry, how many other disciplines use chemistry? |
There are 3. Biology, physics, and geology. |
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What is the name of the field of study involved with chemistry and physics? |
Physical chemistry |
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What is the name of the field involving chemistry and biology? |
Biochemistry |
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The boundaries between scientific disciplines are not rigid. All scientific disciplines borrow information from each other. |
True |
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Chemistry is the study of matter. What is matter? |
Matter is anything that has mass and occupies space. Since matter is anything that has mass and occupy space, we can see many types of matter. However, sometimes matter cannot be seen although it has mass and occupies space. For instance, colorless gasses, Air, water vapour, carbon dioxide, and helium. |
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Matter does not include what? |
Energy, ideas, and feelings, such as heat, light, sound, electricity, love, courage, wisdom, and knowledge. |
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Chemistry deals with 3 basic concepts about matter, what are they? |
The composition of matter, properties of matter, and changes matter under goes. |
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When we study the materials that make up ocean crusts, we are studying the composition of matter. |
True |
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When we determine the hardness of a substance or how fast it evaporates we are studying the Properties of matter. |
True |
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When we evaluate the reaction between new polymers used to make better plastics, we are studying the changes matter undergoes. |
True |
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Do you need to know the composition, properties, and changes matter undergoes before you know it's chemistry? |
Yes |
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Rubber, Vinegar, sugar, and brass are forms of matter that have different what? |
Compositions |
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The manner in which different parts of matter are put together is known as what? |
Structure. Structure gives important information about matters composition. |
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Diamonds and graphite are 2 different types of matter. However, there both made of carbon. What makes diamonds and graphite different kinds of matter? |
Structure |
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What is the 2nd important concept of matter? |
Its properties. Properties are the distinguishing characteristics of a substance. Chemical substances can be identified by their properties. |
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Each chemical substance has a unique set of properties that distinguishes it from all other substances. If 2 substances have identical properties they are the same what? |
Substance |
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What are the 2 general kinds of properties? |
Physical and chemical |
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Physical properties |
These are observed without attempting to change a substance into a new substance. |
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Chemical properties |
These are observed when attempting to change a substance into a new substance. |
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When observing a physical property, a substance may change appearance but its identity will not change. For example, the melting point of ice cannot be measured without changing the ice to illiquid. Although the liquid waters Appearance is much different than ice, it is still the same substance, water. The melting point is What property of matter? |
Physical. When observing a physical property, a substance may change form but its composition does not change because it is still the same substance. |
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Chemical properties are observed when attempting to change a substance into a new substance. Often, these chemical changes result from interaction with another substance. Give an example. |
Iron objects left outside Will interact with the water and oxygen in the atmosphere and the resulting rust on the iron is a new substance. Therefore, rusting is a chemical property. |
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The failure of a substance to undergo a reaction is also considered a chemical property. For instance, both flammability and non flammability are chemical properties. Goal does not react with water. What kind of property is this? |
Chemical |
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The 3rd concept of matter is the changes it undergoes. Changes in matter are classified as what? |
Physical change and chemical change |
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Physical change |
A process that does not alter the composition of a substance. |
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Chemical change |
A process that changes the composition of a substance. |
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When wheat is ground into flour, what kind of change occurs? |
A Physical change. Changes in size and shape of a substance are examples of physical changes. |
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When wood is burnt it is turned to ash. What type of change is this? |
Chemical, The composition has been altered. |
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The formation of one or more new substances is always a characteristic of chemical change. |
True |
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Some chemical changes are beneficial because new useful products are formed. How about the rusting of iron? |
No, there is nothing useful about rust. But by studying the way matter changes, chemist learn how to produce favorable Changes and prevent undesirable changes in Matter. |
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Scientific method |
A logical process used to acquire new knowledge in any science. The majority of science knowledge and technological advances have resulted from experimentation when using the scientific method. Most scientific discoveries are made by experimentation. |
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What are the 4 basic parts of the scientific method? |
Problem, facts, hypotheses, and theory. In all parts, however, experimentation occurs between each of them. |
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What is an experiment? |
A procedure for obtaining more information about a problem. |
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What is a fact? |
A scientific fact is a valid observation about some natural event. Scientific facts must be reproducible. |
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What is a hypothesis? |
A tentative explanation why a certain behaviour always occurs. A hypothesis is confirmed through repeated experimentation. |
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What is a theory? |
A theory is a hypothesis that has been tested and validated over a long period of time. |
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What technique of science is used to collect facts, test a hypothesis, and prove a theory? |
Experimentation |
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Can a scientific theory change? |
Yes, if new evidence disproves the theory. Theories are still tentative explanations, not rigid truth. In other words, a theory can never be proven true. |
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What is a law? |
Quite often, repeating patterns become apparent among the collection of facts. These patterns lead to generalisations of natural observations called laws. Thus, a law is a generalised statement that concisely summarises facts about a natural phenomena. Laws are not easy to discover. It often takes years of work and thousands of upon thousands of observations before the true relationship among facts becomes apparent. A law Never explains why something happens. A law only summarises Common sets of observations without trying to clarify why. In contrast, a hypothesis or theory always explains why some natural phenomena occurs. |
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The difference between a law and a fact |
Laws and facts are often confused. A fact is a single observation while a law covers and brings together many common facts. |
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Measurement |
To properly understand and classify matter, its physical and chemical properties must be observed or measured. Scientists often rely on measurements to explain the nature of a substance. |
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There are 2 general types of observations, what are they? |
Qualitative and quantitative |
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Qualitative observation |
A qualitative observation is made using only the senses and is expressed using words rather than numbers. For instance, the food is hot, cotton Burns fast, or gold is shiny. |
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Quantitative observation |
A quantitative observation or measurement produces a number and describes a property in terms of how much. For example, the water temperature is 100ﾟC, or sound travels at 740 miles per hour. Scientists often rely on quantitative measurements To explain the nature of a substance. Measurements determine the quantity, capacity, dimensions, or the extent of a substance. Therefor, one or more quantitative measurement is always part of a complete description of any substance. |
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Measurements always consist of 2 parts, what are they? |
Number and unit. The number tells the amount of the quantity measured and the unit tells the type of quantity measured.To be useful, a measurement must always have a unit. A measurement without a unit is useless. Some of the most common types of measurements made are volume, length, mass, temperature, time, and pressure. The units for these measurements can be different. For example, volume units might be measured in cups, courts, gallons, or leaders. A measurement can be reported as precisely using one unit As another unit. |
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The English and metric system |
Since the French revolution in the 1700s there has been an effort to standardise the units used to make scientific measurements. Most nations of the world have adopted the metric system of measurements. However, the United States still uses the English system in Commerce and industry and the metric system for scientific measurements. |
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The metric system has several advantages over Other measuring systems which makes it easier to use. What are these advantages? |
There is only one basic unit for each type of measurement, meter, liter, Gram, etcetra. Unit smaller or larger than the basic unit differ by factors of 10, the metric system is a decimal system. |
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Because of their convenient sizes, 5 common units are used in chemistry. What are they? |
Meter, m, liter, L, gram, g, degree celsius, °C, calorie, cal. |
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The metric system only has one basic unit for each type of measurement such as length, volume, mass, etc. The basic units are multiplied or divided by powers of 10 to get larger or smaller units. The larger or smaller units have names consisting of a prefix Attach to the basic unit which indicates the powers of 10 used. |
True, A prefix is used to indicate how smaller and larger units in the metric system relate to the basic unit. For instance, a kilometer is larger than a meter and a centimeter is smaller than a meter. |
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Temperature |
Temperature is another important Measurement scientists make. It is difficult to define but easy to measure. There are 3 different temperature scales, Celsius, Fahrenheit, Kelvin. Celsius is the most commonly used temperature scale in scientific work. For instance, the normal freezing point Of water is 0ﾟC and the boiling point is 100ﾟC. Kelvin is also a commonly used temperature scale in scientific work. Kelvin and Celsius are closely related because they have the same size temperature unit. They differ only in the 0 point. 0 on the Kelvin scale corresponds to the lowest temperature known. The unit representing Kelvin is K. In regards to water, the freezing point on the Kelvin scale is 273 K And the boiling point is 373 K. There are 100 units between the freezing and boiling points of water on both the Sophia's and Kelvin scales. Thus, the size of units are the same, since the number of units between the freezing and boiling points are the same.Temperature readings using the Kelvin and Celsius temperature scales differ by 273, Also known as the adjustment factor. |
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Comparing Celsius and Fahrenheit |
The difference between the freezing and boiling point of water on the Celsius scale are 100° and 180° on the Fahrenheit scale. Therefore, the size of the Celsius degree is 1.8 or 9/5 times larger than a Fahrenheit degree. |
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There are 2 equations to convert between Fahrenheit and Celsius temperatures. |
True |
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What is energy? |
The capacity to do work. According to this definition, energy is required to move matter and change its position. For example, energy is required to make a motor run, throw a baseball, move a rock up a Hill, or move electrons through a wire. Matter is easy to recognise because it can be felt in usually seen. However, energy cannot be seen, touched, smelt, or weighed. Energy is experienced through its effect on matter. Residents, you experience the effects of energy when you catch a baseball or stand next to a fire. |
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There are 5 main forms of energy, what are they? |
Mechanical, energy associated with the bulk movement of matter. Thermal, energy associated with random motion of atoms and molecules. Chemical, energy associated with the position of Atoms in a substance. Electromagnetic, energy associated with the moving electrical charges. And nuclear, energy associated with the position of Subatomic particles in the a nucleus. All forms of energy can be inter converted. For instance, sunlight makes you feel warm, electromagnetic energy is changed into thermal energy. When writing a bicycle your muscles make the wheels turn, chemical energy is changed to mechanical energy. Steam in the power plant turns the generator, thermal energy is changed to electromagnetic energy. |
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Law of conservation of energy |
This States that in any chemical or physical change, energy can be converted from one form to another, but it is neither created nor destroyed. Studies of energy changes in numerous systems have shown that no system acquires energy except from the loss of an equal amount of energy from another system. For example, when wood Burns the chemical energy of the wood is changed into heat and light energy. |
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Where does almost all of the energy on Earth originate from? |
From the Sun in the form of radiant or solar, electromagnetic, energy. Green plants convert this radiant energy into chemical energy by means of photosynthesis. Therefor, all energy for the human body is obtained, either directly or indirectly, from the Sun because we consume food for its chemical energy. |
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In addition to the various forms of energy, there are 2 types of energy. What are they? |
Kinetic, energy associated with the movement of matter, and potential, energy associated with the position of matter. 2 of the forms of energy are classified as kinetic energy, they are thermal and mechanical. |
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Potential energy |
Potential energy is the energy associated with the position of matter relative to other matter. For instance, a one kg bawl raised 1 meter above the floor has potential energy with respect to the floor. Therefor, the higher the Ball is raised, the more potential energy it will have. Chemical energy is a form of potential energy because the Atoms in a substance are associated with relative positions or arrangements with respect to other Atoms. When we move our muscles, we convert chemical energy, potential energy stored in our bodies, to kinetic energy. |
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Chemical reactions |
Most energy in the form of chemical Involve either the release or the absorption of energy. Therefor, it has potential energy. Most chemical reactions, however, involve energy changes in the form of heat, thermal energy. The thermal energy Alters the chemical energy and converts the potential energy into kinetic energy. |
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The metric system unit for measuring energy is known as what? |
Joule (J). A flashlight uses about one Joule of energy for every 2nd and a typical household in the United States uses several billion joules of Electricity every month. |
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Calorie |
The form of energy most often measured is heat energy. A common unit used to report heat energy is the calorie (cal). A calorie is the amount of heat energy needed to increase the temperature of one g of water 1ﾟC. The calorie and jewel are both measures of energy And are related as one calorie for every 4.184 jewels. We commonly talk about the energy content of food. A nutritional or food calorie is actually 1000 calories or one (kcal). The food calorie is spelt with a capital (C) and the symbol is (Cal). |
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What is the dimensional analysys method? |
Many problems in chemistry can be solved using a systematic approach called the dimensional analysis method. Central to the use of dimensional analysis is the conversion of one unit or quantity to another unit or quantity. Dimensional analysis method uses the units associated with numbers as a guide in setting up calculations. In this method, units are treated the same as numbers. They can be multiplied, divided, cancelled, etc. For instance, mL x mL= mL2. There are 4 basic steps in the dimensional analysis method. They are identify the known and desired quantities, write down the known quantity and leave some working space by drawing a horizontal line and set the known quantity equal to units of the desired quantity, determined the conversion factor for the equation, carry out the necessary arithmetic to solve the problem. There are always 2 conversion factors for any relationship. The units in an equation determine the conversion factor. |
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Density |
Density is defined as the mass per volume of the sample of matter. Substances are often compared by stating that 1 object is heavier than another. What actually needs to be compared is there densities. Although any mass and volume units can be used, densities are usually expressed in solids g/cm3, liquids g/mL, and gases g/L. Conversely, if the density is known, the mass of a substance can be calculated from its volume. |
