Matter

Question 1

Substance

Answer 1

a type of matter with a fixed composition

Question 2

element

Answer 2

all atoms in a substance have the same identity

Question 3

compound

Answer 3

a substance in which the atoms or two more elements are combined in a fixed proportion

Question 4

heterogeneous mixture

Answer 4

a mixture in which different materials can be distinguished easily

Question 5

homogeneous mixture

Answer 5

two or more gaseous liquid or solid substances blended evenly throughout

Question 6

solution

Answer 6

a homogeneous mixture of particles so small that they cannot be seen with a microscope and will never settle to the bottom of their container

Question 7

colloid

Answer 7

mixture with particles larger than those in solutions but not heavy enough to settle out

Question 8

Tyndall effect

Answer 8

scattering of light by colloidal particals

Question 9

suspension

Answer 9

heterogeneous mixture containing a liquid in which visible particles settle

Question 10

physical property

Answer 10

characteristics of a material that you can observe without changing the identity that make up the material

Question 11

physical change

Answer 11

change in shape size or state of matter

Question 12

distillation

Answer 12

separating substances in a mixture by evaporating a liquid and recondensing its vapor

Question 13

chemical property

Answer 13

characteristic of a substance that indicates whether it can undergo a certain chemical change

Question 14

chemical change

Answer 14

a change of one substance to another

Question 15

law of conservation of mass

Answer 15

the mass of all substances that are present before a chemical change equals the mass of all substances that remain

Question 16

kinetic theory

Answer 16

how particles in matter behave

Question 17

melting point

Answer 17

temperature at which a solid begins to liquefy

Question 18

heat of fusion

Answer 18

the amount of energy required to change a substance from the solid phase to liquid phase

Question 19

boiling point

Answer 19

temperature at which the pressure of the vapor in the liquid is equal to the external pressure acting on the surface of the liquid

Question 20

heat of vaporization

Answer 20

amount of energy required for the liquid at its boiling point to become gas

Question 21

diffusion

Answer 21

spreading of particles throughout a given volume until they are uniformly distributed

Question 22

plasma

Answer 22

matter consisting of positive and negatively charged particles

Question 23

thermal expansion

Answer 23

an increase in the size of a substance when the temperature is increased

Question 24

buoyancy

Answer 24

the ability of a fluid, liquid or gas to exert an upward force on an object immersed in it

Question 25

pressure

Answer 25

force exerted per unit area

Question 26

viscosity

Answer 26

the resistance to flow by a fluid

Question 27

pascal

Answer 27

unit of pressure