Particle theory for Pure Substances and Mixtures

Question 1

change of state

Answer 1

change from one of the three states of matter to another (202)

Question 2

condensation

Answer 2

change of state from a gas to a liquid when heat is removed (203)

Question 3

deposition

Answer 3

change from the gas state directly to the solid state; it involves removing energy (203)

Question 4

dissolve

Answer 4

mix a substance (solute) with another substance (solvent) to form a solution (e.g., salt with water) (196)

Question 5

evaporation (vaporization)

Answer 5

change of state from a liquid to a gas; it involves adding heat; also called vaporization (203)

Question 6

freezing (solidification)

Answer 6

change of state from a liquid to a solid; it involves losing heat; also called solidification (203)

Question 7

gas

Answer 7

matter that does not have a definite shape or volume; the particles in a gas are widely separated and can move freely (194)

Question 8

heat

Answer 8

thermal energy transferred from a solid, a liquid, or a gas at a higher temperature to a solid, a liquid, or
a gas at a lower temperature; also refers to the thermal energy that transfers within a solid, a liquid, or a gas (201)

Question 9

heterogeneous

Answer 9

term used to describe a substance that does not appear uniform throughout (196)

Question 10

homogeneous

Answer 10

term used to describe a substance that appears uniform throughout (195)

Question 11

kinetic energy

Answer 11

energy that an object or system has because of its motion; particles of matter have kinetic energy (200)

Question 12

liquid

Answer 12

matter that does not have a definite shape but does have a definite volume; the particles in a liquid are close together but can move easily around each other (194)

Question 13

matter

Answer 13

anything that has mass and takes up space; can be classified by its physical state (solid, liquid, or gas) and by composition (pure substance or mixture) (194)

Question 14

mechanical mixture

Answer 14

heterogeneous mixture; a mixture made up of many different substances, each with a different appearance and properties; a heterogeneous mixture does not have a uniform composition (196)

Question 15

melting

Answer 15

change of state from a solid to a liquid; it involves adding heat (203)

Question 16

mixture

Answer 16

combination of two or more different substances; the substances are not chemically combined and may be separated again (195)

Question 17

particle

Answer 17

very small portion of matter that cannot be seen with the eyes alone (199)

Question 18

particle theory of matter

Answer 18

theory that states that all matter is made up of particles; that all particles of one substance are identical; that particles of matter are in constant motion; that temperature affects the speed at which particles move; that particles have forces of attraction between them; and that there are spaces between particles; this theory explains the behaviour of solids, liquids, and gases (200)

Question 19

pure substance

Answer 19

matter that has uniform properties and is one type of substance throughout (195)

Question 20

solid

Answer 20

matter that has a definite shape and volume; in a solid, the particles are packed tightly together and vibrate in place (194)

Question 21

solidification

Answer 21

change of state from a liquid or gas to a solid; it involves removing heat; also called freezing (203)

Question 22

solution

Answer 22

homogeneous mixture of two or more substances, which may be solids, liquids, or gases or a combination of these (196)

Question 23

sublimation

Answer 23

change from the solid state directly to the gas state; it involves adding energy (203)

Question 24

temperature

Answer 24

measurement of the average kinetic energy of the particles in a substance (201)