Chem - Ch 2

Question 1

extensive property

Answer 1

a property that depends on the amount of matter in a sample

Question 2

intensive property

Answer 2

a property that depends on the type of matter in a sample, not on the amount of matter

Question 3

(pure) substance

Answer 3

matter that has a uniform and definite composition

either an element or a compound

Question 4

What’s a good ‘test’ to see if something is a substance

Answer 4

if you’d reach your hand in, you’d get the same stuff every time

Question 5

physical property

Answer 5

a quality or condition of a substance that can be observed or measured without changing the substance’s composition

Question 6

solid

Answer 6

a form of matter that has a definite shape and volume

Question 7

how are the individual particles arranged in a solid

Answer 7

packed closely together in a rigid arrangement

Question 8

how are the individual particles arranged in a liquid

Answer 8

close together, but they are free to flow past each other

Question 9

how are the individual particles arranged in a liquid

Answer 9

particles are relatively far apart and can move freely

Question 10

liquid

Answer 10

a form of matter that flows, has a fixed volume, and an indefinite shape

Question 11

gas

Answer 11

a form of matter that takes the shape and volume of its container; has no definite shape of volume

Question 12

physical change

Answer 12

a change in which the appearance changes, but the composition does not

Question 13

chemical change

Answer 13

a change in which there is a composition change

Question 14

examples of physical change

Answer 14

melting, boiling, breaking, cutting, dissolving, state changes

Question 15

is there any kind of chemical reaction taking place in a physical change

Answer 15

no

Question 16

are physical changes often reversible or irreversible

Answer 16

reversible

Question 17

signs of chemical change

Answer 17

produces bubbles, turns cloudy, temperature change, color change, change in smell or taste,

Question 18

examples of chemical change

Answer 18

baking cookies, nail/penny rusting, fireflies glowing, burning gas, fire

Question 19

Why do all samples of a given substance have the same intensive properties?

Answer 19

because a substance has a definite composition so the matter in each sample will be the same. Intensive properties depend on the type of matter, and not on the amount of it.

Question 20

Describe a reversible physical change

Answer 20

something can be done to get it back the way it was before

Question 21

Describe an irreversible change

Answer 21

nothing can be done to get it back the way it was before

Question 22

How are liquids and gasses alike?

Answer 22

they both take the shape of their container

Question 23

How are liquids and solids different?

Answer 23

a solid has a definite shape, a liquid has an indefinite shape

Question 24

list the 3 states of matter in order of density

Answer 24

solid, liquid, gas

Question 25

mixture

Answer 25

2 or more substances physically combined | not pure

Question 26

heterogeneous mixture

Answer 26

not uniform in composition | components are not evenly distributed throughout the mixture

Question 27

examples of heterogenous mixture

Answer 27

ice cubes in liquid water mashed, unpeeled potatoes salad sand

Question 28

homogenous mixture

Answer 28

uniform in composition | components are evenly distributed and not easily distinguished

Question 29

examples of homogenous mixture

Answer 29

green ink mouthwash salt water air

Question 30

how can you tell what kind of a mixture it is

Answer 30

do spoon test - if you took 2 spoonfuls of the same mixture and if it looks like the same thing in each spoon, then its homo. if not, then its hetero

Question 31

solution

Answer 31

a homogenous mixture

Question 32

filtration

Answer 32

a process that separates a solid from the liquid in a heterogeneous mixture

Question 33

distillation

Answer 33

a process used to separate components of a mixture using differences in boiling points

Question 34

how is distillation accomplished

Answer 34

by boiling a liquid to produce a vapor. This vapor is then channeled into a condenser that has a cooling coil around it. This turns the vapor back into a liquid. The solid substances that were dissolved in the liquid remain in where they were because their boiling points were higher

Question 35

how are a substance and a solution similar

Answer 35

they both have a uniform composition

Question 36

how are a substance and a solution different

Answer 36

a substance is pure (an element or a compound) but a solution is not pure and is always a mixture of two or more things

Question 37

What are some ways to separate a mixture

Answer 37

distillation, filtration, evaporation, use a magnet, diff melting temps, pick apart by hand, dissolving, extracting based on solubility, diff densities

Question 38

element

Answer 38

simplest form of matter with a unique set of properties | cannot be broken down into simpler substances by chemical means

Question 39

compound

Answer 39

a substance that contains two or more elements chemically combined in a fixed proportion

Question 40

How is a compound different from an element?

Answer 40

An element is the simplest form of matter that has a unique set of properties, while a compound is a substance that contains 2 or more elements chemically combined. Compounds can be broken down into simpler substances by chemical means, but elements can't.

Question 41

table salt - compound, element, or mixture? why?

Answer 41

compound because it is made of two elements chemically combined

Question 42

salt water - compound, element, or mixture? why?

Answer 42

mixture because it is made of two compounds

Question 43

sodium - compound, element, or mixture?

Answer 43

element bc it is not combined with any other element

Question 44

what does H20 tell you about the composition of water

Answer 44

the compound water contains two parts hydrogen to one part oxygen

Question 45

chemical property

Answer 45

the ability of a substance to undergo a specific chemical change

Question 46

chemical reaction

Answer 46

a change in which one or more reactants change into one or more products

Question 47

reactant

Answer 47

a substance present at the start of a reaction

Question 48

product

Answer 48

a substance produced in a chemical reaction

Question 49

law of conservation of mass

Answer 49

in any physical change or chemical reaction, mass is conserved; mass can neither be created nor destroyed

Question 50

name 4 possible clues that a chem change has taken place

Answer 50

transfer of energy a change in color the production of a gas the formation of a precipitate

Question 51

In a chemical reaction, how does the mass of the reactants compare to the mass of the products?

Answer 51

In any chemical reaction, the mass of the products is always equal to the mass of the reactants because of the law of conservation of mass

Question 52

water boils - physical or chemical change? clue?

Answer 52

physical

Question 53

charcoal burns in a grill - physical or chemical change? clue?

Answer 53

chemical (color change)

Question 54

bread dough rises when yeast is added - physical or chemical change? clue?

Answer 54

chemical (production of a gas)

Question 55

brittle - chemical or physical property?

Answer 55

physical

Question 56

melts at 140 degrees - chemical or physical property?

Answer 56

physical

Question 57

What is it called when a solid changes to a liquid

Answer 57

Melting

Question 57

What is it called when a solid changes to a liquid

Answer 57

Melting

Question 58

What is it called when a liquid changes to a gas

Answer 58

Boiling Vaporizing Evaporating

Question 59

What is it called when a solid goes directly to a gas

Answer 59

Sublimining

Question 60

What is it called when a gas goes directly to a solid

Answer 60

Depositing

Question 61

What is it called when a gas changes to a liquid

Answer 61

Condensing

Question 62

What is it called when a liquid changes to a solid

Answer 62

Solidifying | Freezing