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Question 1

qualitative quantity

Answer 1

non-numerical info

Question 2

quantitative quantity

Answer 2

numerical info

Question 3

physical property

Answer 3

property that can be found without creating new substances

Question 4

chemical property

Answer 4

the ability of a substance to undergo a chemical reaction and change into a new substance, either by itself or with other substances

Question 5

Dif between atom and molecule

Answer 5

atom- smaller possible unit of an element which retains the fundamental properties of the element. molecule- cluster of 2 or more atoms, held together strongly by electrical forces

Question 6

homogenous mixture

Answer 6

substance consisting of only 1 phase

Question 7

heterogenous mixture

Answer 7

substance consisting of more than 1 phase

Question 8

solvent

Answer 8

the part of a solution that exists in a greater quantity

Question 9

solute

Answer 9

the component in a solution which exists in a smaller quantity

Question 10

what part of mixture is called the residue after filtration

Answer 10

the leftovers in the filter paper

Question 11

what part of mixture is called filtrate after filtration

Answer 11

the liquid at the bottom

Question 12

what kind of mixtures can you separate using evaporation

Answer 12

liquids with dissolved solids

Question 13

what is dif between evaporation and distillation

Answer 13

evaporation- to separate dissolved solids from liquids (does not retain liquid portion)
distillation- separation technique based on differences in boiling points.

Question 14

what’s lab ethanol and why shouldn’t you drink it

Answer 14

there could be methanol in it. you’ll go blind and then you’ll die.

Question 15

what is equipment used in gravity separation called

Answer 15

centrifuge

Question 16

what property of matter does chromatography use to separate mixtures

Answer 16

differential solubility

Question 17

what is wrong with a calculated RF value of 1.2?

Answer 17

RF is rate of distance travelled by the solute/ rate of distance travelled by the solvent, and the solvent always travels farther than the solute.

Question 18

on a temp vs time graph, what’s happening when the graph is sloping?

Answer 18

temp increases as more heat is added to the system

Question 19

on a temp vs time graph, what’s happening when graph is flat?

Answer 19

for a period of time, the temperature remains constant even as heat is being added.

Question 20

crystals

Answer 20

pure substances. regular shape, sharp edges

Question 21

solid

Answer 21

• mainly vibrational energy = Ev

- high intermolecular force

Question 22

liquid

Answer 22

• transitional energy= Et
• rotational energy, Er and Ev
• intermolecular forces present but decreased from solid state

Question 23

gas

Answer 23

• high energy particles
• move very fast
• no intermolecular forces

Question 24

hand separation

Answer 24

stuff like sieves, magnets

Question 25

filtration

Answer 25

to separate an undissolved solid from a liquid

Question 26

solvent extraction

Answer 26

• to separate a soluble solid from a mixture (like a mixture of salt and sand)

Question 27

how would you separate sand and salt

Answer 27

solvent extraction:

1) add water, now it is salt water with sand in it
2) filter sand from salt water
3) boil water out of sand

Question 28

recrystallization

Answer 28

to separate a dissolved ionic compound from a liquid

Question 29

gravity separation

Answer 29

to separate substances based on density

Question 30

chromatography

Answer 30

• to separate substances based on differential solubility

- the more soluble a substance is, the further it will travel with the solvent

Question 31

what is the RF formula and what do the components represent

Answer 31

D1/D2

distance travelled by solute/ distance travelled by solvent

Question 32

freezing point

Answer 32

• the temperature at which a liquid changes into a solid

- at this temperature, the solid and liquid phases co-exist

Question 33

precipitate

Answer 33

a solid formed when 2 liquids or aqueous solutions react

Question 34

suspension

Answer 34

a heterogenous mixture in which solute-like particles settle out of a solvent-like phase sometime after they are introduced

Question 35

melting point

Answer 35

• the temperature at which a solid changes into a liquid

- at this temperature, the solid and liquid phases co-exist

Question 36

solution

Answer 36

a homogenous mixture of 2 or more substances

Question 37

mixture

Answer 37

a system made up of 2 or more pure substances, such that the relative amounts of each substance can be varied

Question 38

mechanical mixture

Answer 38

a heterogenous mixture of 2 or more substances

Question 39

compound

Answer 39

a pure substance made up of two or more types of atoms

Question 40

extensive property

Answer 40

a physical property which depends on how much of a substance is present

Question 41

intensive property

Answer 41

a physical property which depends only on the nature of the substance

Question 42

kinetic molecular theory

Answer 42

states that gas particles are in constant motion and exhibit perfectly elastic collisions

Question 43

mass

Answer 43

the quantity of matter in an object

Question 44

boiling point

Answer 44

the temperature at which a liquid changes into a gas. at this point, the liquid and gas phases co-exist

Question 45

element

Answer 45

a substance which cannot be separated into simpler substances as a result of any chemical processes

Question 46

pure substance

Answer 46

a homogenous substance that has an unchangeable composition

Question 47

chemical changes

Answer 47

changes in which new substances are formed

Question 48

physical changes

Answer 48

changes in substance phases that do not create new substances