Chemistry Unit 2 Vocabulary

Question 1

Chemistry

Answer 1

the branch of science that deals with the identification of the substances of which matter is composed; the investigation of their properties and the ways in which they interact, combine, and change; and the use of these processes to form new substances.

Question 2

Matter

Answer 2

physical substance in general, as distinct from mind and spirit; (in physics) that which occupies space and possesses rest mass, especially as distinct from energy.

Question 3

Extensive Properties

Answer 3

Extensive properties, such as mass and volume, depend on the amount of matter that is being measured

Question 4

Intensive Properties

Answer 4

Intensive properties, such as density and color, do not depend on the amount of matter.

Question 5

Mass

Answer 5

Mass is a measure of the amount of matter in an object. Mass is usually measured in grams (g) or kilograms (kg).

Question 6

Volume

Answer 6

Volume is the quantity of three-dimensional space occupied by a liquid, solid, or gas.

Question 7

Physical Properties

Answer 7

A physical property is any property that is measurable, whose value describes a state of a physical system. The changes in the physical properties of a system can be used to describe its transformations or evolutions between its momentary states. Physical properties are often referred to as observables.

Question 8

Physical Change

Answer 8

Physical changes are changes affecting the form of a chemical substance, but not its chemical composition. Physical changes are used to separate mixtures into their component compounds, but can not usually be used to separate compounds into chemical elements or simpler compounds.

Question 9

Chemical Property

Answer 9

property or characteristic of a substance that is observed during a reaction in which the chemical composition or identity of the substance is changed: Combustibility is an important chemical property to consider when choosing building materials.

Question 10

Chemical Change

Answer 10

Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances.

Question 11

Phase (phase of matter)

Answer 11

The states in which matter can exist: as a solid, liquid, or gas. When temperature changes, matter can undergo a phase change, shifting from one form to another.

Question 12

Solid

Answer 12

A solid is a state of matter characterized by particles arranged such that their shape and volume are relatively stable. The constituents of a solid tend to be packed together much closer than the particles in a gas or liquid

Question 13

liquid

Answer 13

A liquid is one of the states of matter. The particles in a liquid are free to flow, so while a liquid has a definite volume, it does not have a definite shape. Liquids consists of atoms or molecules that are connected by intermolecular bonds

Question 14

Gas

Answer 14

gas has no fixed shape and will take on the shape of the space available. Unlike a liquid, the intermolecular forces are very small; it has no fixed volume and will expand to fill the space available.

Question 15

Freezing

Answer 15

The process through which a substance changes from a liquid to a solid. All liquids except helium undergo freezing when the temperature becomes sufficiently cold.

Question 16

Melting

Answer 16

Melting, or fusion, is a physical process that results in the phase transition of a substance from a solid to a liquid. This occurs when the internal energy of the solid increases, typically by the application of heat or pressure, which increases the substance’s temperature to the melting point.

Question 17

Vaporization

Answer 17

Vaporization (or vapourisation) of an element or compound is a phase transition from the liquid phase to vapor.

Question 18

Condensation

Answer 18

Condensation is the process of a substance in a gaseous state transforming into a liquid state. This change is caused by a change in pressure and temperature of the substance.

Question 19

Sublimation

Answer 19

Sublimation is a type of phase transition, or a change in a state of matter, just like melting, freezing, and evaporation. Through sublimation, a substance changes from a solid to a gas without ever passing through a liquid phase

Question 20

Deposition

Answer 20

The direct solidification of a vapor by cooling; the reverse of sublimation.

Question 21

Substance

Answer 21

A substance is matter which has a specific composition and specific properties. Every pure element is a substance. Every pure compound is a substance. Examples of substances: Iron is an element and hence is also a substance.

Question 22

Element

Answer 22

An element is composed of atoms that have the same atomic number, that is, each atom has the same number of protons in its nucleus as all other atoms of that element.

Question 23

Chemical Symbol

Answer 23

chemical symbol. noun. an abbreviation or short representation of a chemical element; the symbols in the periodic table. Natural elements all have chemical symbols of one or two letters; some manmade elements have three-letter symbols.

Question 24

Compound

Answer 24

A compound is a substance formed when two or more chemical elements are chemically bonded together. … Water: two hydrogen atoms bonded to an oxygen atom. The type of bonds holding elements together in a compound can vary: two common types are covalent bonds and ionic bonds.

Question 25

Mixture

Answer 25

Any substance that has a uniform and unchanging composition is considered to be pure. Examples of pure substances include elements. A mixture is a combination of two or more pure substances in which each pure substance retains its individual chemical properties.

Question 26

Homogeneous MIxture

Answer 26

An example of a homogeneous mixture is air. In physical chemistry and materials science that refers to substances and mixtures which are in a single phase. This is in contrast to a substance that is heterogeneous.

Question 27

Solution

Answer 27

In chemistry, a solution is a homogeneous mixture composed of two or more substances. In such a mixture, a solute is a substance dissolved in another substance, known as a solvent.

Question 28

Heterogeneous Mixture

Answer 28

A mixture is a combination of two or more pure substances in which the original substances retain their chemical properties. In some mixtures, the initial substances cannot be detected after they have been mixed.

Question 29

Filtration

Answer 29

Filtration is any of various mechanical, physical or biological operations that separate solids from fluids (liquids or gases) by adding a medium through which only the fluid can pass. The fluid that passes through is called the filtrate.

Question 30

Distillation

Answer 30

distillation can be used to purify water or other substances, or to remove one component from a complex mixture, as when gasoline is distilled from crude oil or alcohol from a mash.

Question 31

Chemical reaction

Answer 31

Chemical reaction, a process in which one or more substances, the reactants, are converted to one or more different substances, the products. Substances are either chemical elements or compounds. A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.

Question 32

Reactant

Answer 32

a substance that takes part in and undergoes change during a reaction.

Question 33

Products

Answer 33

Products are the species formed from chemical reactions. During a chemical reaction reactants are transformed into products after passing through a high energy transition state.

Question 34

Precipitate

Answer 34

cause (a substance) to be deposited in solid form from a solution.

Question 35

Law of conservation of mass

Answer 35

The law of conservation of mass states that mass is neither created nor destroyed. In a closed system, mass of reactants is equal to mass of products.