Natural Sciences Ch 2 Chemistry

Front 1

Define Chemistry

Back 1

is the science concerned with the composition and properties of substances as well as interaction in which these substances play a part.

Front 2

Solids consist of

Back 2

atoms or molecules that are highly attracted to one another, more so than those in liquids and gases.

Front 3

Crystalline solids

Back 3

consist of atoms that are arranged in repeated and definite geometric patterns.

Front 4

Amorphous soldis

Back 4

do not possess atoms arranged in repeated and definite geometric patterns.

Front 5

Gases consist of

Back 5

atoms or molecules with the weakest attraction of any of the three states of matter.

Front 6

When the temperature is increased to a level known as the ________ __________, the element will turn from a solid into a liquid.

Back 6

melting point

Front 7

When the temperature is raised to the ________ _________ the element will go from the liquid state to the gas state.

Back 7

boiling point

Front 8

Some elements can pass directly from the solid to the gaseous state and vice versa through a process called

Back 8

sublimation

Front 9

Define antimatter

Back 9

Does not naturally exist on earth, for if antimatter and ordinary matter came into contact, they would annihilate each other and turn into energy.

Front 10

The ___________ is the simplest form of matter that cannot be reduced by chemical means.

Back 10

element

Front 11

The basic structural unit of the element is the _______

Back 11

atom

Front 12

Define atomic number

Back 12

the number of protons in their nucleus.

Front 13

An _________ is an atom of a particular element that differs from other atoms of the same element in terms of the number of neutrons in its nucleus.

Back 13

isotope

Front 14

The __________ __________ of an element is the combined weight of the protons and neutrons in its nucleus plus the weight of the electrons spinning around the nucleus

Back 14

atomic weight.

Front 15

The basic standard of measurement for atomic weight is the _______ ________ ______ also known as __ __ __

Back 15

Atomic mass unit
AMU

Front 16

Atoms of two or more elements can be combined to form a

Back 16

compound

Front 17

The basic unit of the compound is the

Back 17

molecule

Front 18

________ (liquid) can be formed bye the combination of two or molecules.

Back 18

mixtures

Front 19

Name those mixtures that are too closely combined to be distinguished by sight.

Back 19

Homogeneous mixtures

Front 20

Name those mixtures with components that are coarse enough to be distinguished by the naked eye.

Back 20

Heterogeneous mixtures

Front 21

Define mole

Back 21

is the weight in grams equal to the numerical molecular or atomic weight of a compound or element in atomic mass units.

Front 22

Define molar solution

Back 22

is a solution that consists of one mole of an element or compound dissolved in one liter of water.

Front 23

Define organic compounds

Back 23

are those that contain carbon as one of their base elements.

Front 24

Inorganic compounds

Back 24

Those compounds that do not contain carbon in their base element.s

Front 25

Define acid

Back 25

is a compound that produces positively charged hydrogen ions when it dissociates in water.

Front 26

Define base

Back 26

is and inorganic compound that produces negatively charged hydroxide ions when dissolved in water.

Front 27

Define salt

Back 27

is a compound that is produced bye the reaction of an acid and base when the two are mixed in a water solution.

Front 28

Define pH

Back 28

Potential hydrogen

Front 29

Describe Acid as in relation to the pH scale

Back 29

Increased # of Hydrogen ions
Decrease in the value of pH

Front 30

Describe Base as in relation to the pH scale.

Back 30

Decreased # of Hydrogen ions
Increase in the value of pH

Front 31

Define electrovalence

Back 31

is the process by which electrons are transferred from one atom to another in order to from ions.

Front 32

The _________ ________ of an atom is the number of electrons that would have to be added to or taken from the ion of that atom in order to render it electrically neutral.

Back 32

oxidation number

Front 33

________ occurs when an atom or molecule reacts with other atoms or molecules by removing electrons from the.

Back 33

Oxidation

Front 34

_________ takes place when an atom or molecule reacts with other atoms or molecules by adding electrons to them.

Back 34

Reduction

Front 35

Define hydrolysis

Back 35

is the reaction of a chemical compound with water.

Front 36

When heat is produced in a reaction, that reaction is said to be

Back 36

exothermic

Front 37

When heat is lost or consumed in a reaction, that reaction is said to be

Back 37

endothermic

Front 38

Define the Hess Law of Constant Heat Summation

Back 38

As long as the same product results, however, the sum of the heat released or consumed by each reaction path is the same, regardless of the number and kinds of reaction upon each path.

Front 39

Define solution

Back 39

is a homogeneous mixture of two or more substances.

Front 40

In solutions, the substance being dissolved is called the

Back 40

solute

Front 41

The substance that does the dissolving is known as the

Back 41

solvent

Front 42

A majority of solutions contain water as their solvent, such mixtures are known as

Back 42

Aqueous solutions (aq)

Front 43

Define Henry's law

Back 43

This law states that at a constant temperature, the weight of a gas dissolved in a given weight of liquid is directly proportional to the pressure of that gas at the surface of the liquid.

Front 44

Define electrolyte

Back 44

is any acidic, basic, or salt solution that will conduct electricity because of the charges on its ions.

Front 45

Define polar solvent

Back 45

Atoms of this molecule may be arranged such that the centers of positive and negative charge are located at different points on the molecule.

Front 46

Define dipolar arrangement

Back 46

one end of the molecule is positive and the other is negative (polar solvent)

Front 47

Define nonpolar solvent

Back 47

is one in which the solvent molecules are symmetrical and have their centers of positive and negative charge in the same location

Front 48

A solution is _____________ is one in which, at a given temperature, the number of molecules or ions of solute dissolving into solution from the solid state is exactly the same as the number going back into the solid state from solution.

Back 48

Equilibrium

Front 49

___________ is a measure of the amount of solute in a given volume of solution.

Back 49

Concentration