quiz 2

Question 1

mass

Answer 1

the amount of matter in an object, independent of gravity

measured using grams

Question 2

weight

Answer 2

a measure of the pull of gravity on an object

measured in newtons or pounds

Question 3

volume of a rectangle

Answer 3

lwh

usually in cm^3

Question 4

density

Answer 4

mass (g)/volume (mL)
if an object is less dense than its surroundings, it floats
if an object is the same density, it is suspended
if an object is more dense, it sinks

Question 5

how can you measure the volume of an oddly shaped object?

Answer 5

submerge it in water. the amount of water displaced = volume

Question 6

an intensive property

Answer 6

property is independent of the amount of substance

density is intensive

Question 7

extensive property

Answer 7

property is dependent on amount of substance

mass and volume are extensive

Question 8

matter

Answer 8

anything that occupies space and has mass

Question 9

heterogeneous

Answer 9

mixture is not uniform throughout

Question 10

homogenous

Answer 10

mixture is uniform throughout

Question 11

compound

Answer 11

comprised of two or more elements

Question 12

smallest unit of a compound

Answer 12

molecule

Question 13

atoms

Answer 13

make up molecules and are connected through bonds. if it is cut, the results is subatomic particles

Question 14

3 states of matter

Answer 14

solid, liquid, gas

bonus: aqueous, but it requires water and thus the matter is no longer pure

Question 15

physical property

Answer 15

property that matter displays without changing its composition (chemical formula)
it is reversible
ex: color, malleability, conducting electricity, physical properties due to evaporation/condensation or freezing

Question 16

chemical property

Answer 16

a property that matter displays with a change in its composition
usual markers:
-color change
-production of odor
-change of temperature
-evolution of gas
-precipitation

Question 17

principle of the conservation of mass

Answer 17

mass is neither created nor destroyed

Question 18

energy

Answer 18

is the capacity to do work and is not a form of matter since it does not have mass

Question 19

law of conservation of energy

Answer 19

energy can neither be created nor destroyed. instead, there are only transfers of energy and changes of forms

Question 20

kinetic energy

Answer 20

energy of motion

Question 21

potential energy

Answer 21

stored energy

Question 22

exothermic reaction

Answer 22

a reaction in which:

• heat EXits the reaction (ie hot pack)
• energy/heat is a product in a chemical reaction
• the reactants themselves contain more energy than the products

Question 23

endothermic

Answer 23

a reaction in which:

• heat ENters the reaction (ie cold pack)
• energy/heat is a reactant in a chemical reaction
• the products themselves contain more energy than the reactants

Question 24

the amount of heat required to raise the temperature of a substance is given by

Answer 24

Q=MC∆T
where q= the amount of joules required, M= the mass of the substance IN GRAMS, C= heat capacity of the substance (j/gc), ∆T= desired change in temperature IN CELSIUS

Question 25

the chemicals that you start with in a chemical reaction are the

Answer 25

reactants

Question 26

the chemicals that you end up with in a chemical reaction are the

Answer 26

products

Question 27

1 mL = this cubic length measurement

Answer 27

1 mL = cm^3

Question 28

the density of water is unique in that

Answer 28

it goes down when the temperature decreases, as its volume (the denominator in d) increases
for most other substances, as temp decreases, density increases as their volume decreases