Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chemistry 2 > Seperating Mixtures > Flashcards

Seperating Mixtures Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Chemistry flashcards Periodic Table flashcards Chemistry 101 flashcards Organic Chemistry 101 flashcards
1
Q

What does pure mean?

A

Single element of compound not mixed with anything

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the everyday meaning of pure?

A

Good or moral

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does impure mean?

A

Something containing more than 1 element

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is an element?

A

A substance made from only 1 type of atom

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is a melting point?

A

Temperature at which solid changes into a liquid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is a boiling point?

A

Temperature at which liquid changes to a gas?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the difference in the melting and boiling points between pure and impure substances?

A

Pure substances have higher melting and boiling points

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is filtration?

A

A process used to separate an insoluble solid from a liquid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does soluble mean?

A

Ability of a substance to dissolve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the steps for filtration?

A

Place mixture of solid and liquid in one beaker, and funnel with filter paper in the other. Pour mixture into funnel and observe as solid particles are caught by filter paper

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Why is filtration successful?

A

Because filter paper has tiny holes called pores that allow dissolved particles to enter, but not undissolved particles(and therefore, the particles of the solid)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is crystallisation?

A

Process used to produce solid crystals from a solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the steps for crystallisation?

A

Place solution in an evaporating basin. Heat the basin with a Bunsen burner. Observe as water evaporates and only soluble particles are left behind

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is simple distillation?

A

Process used to separate a solvent from a solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the steps for simple distillation?

A

Heat solution with Bunsen burner; salt will remain as it is while water will become water vapour. Connect flask of solution with condenser and place beaker under other end of condenser. Observe as vapour rises into condenser which cools it with cooling water, making it liquid again, before pure water drops into beaker

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why is simple distillation successful?

A

Because the dissolved water has a much higher boiling point than the solution it comes from

17
Q

What is fractional distillation?

A

Process used to separate different liquids from a mixture of liquids

18
Q

What are the steps for fractional distillation?

A

Heat conical flask of solution with Bunsen burner till liquids reach their boiling points, place a fractionating column in flask and connect column to a condenser which has one end over a beaker and put thermometer in column, observe as water vapour rises through column(which is hot at bottom and cooler at top) and liquids that condense drip back into flask while water vapour that reaches top of column enters condenser, before water vapour becomes liquid in condenser and falls into beaker

19
Q

What is paper chromatography?

A

Process used to separate mixtures of soluble substances

20
Q

What is paper chromatography often used on?

A

Food colourings, inks and plant pigments

21
Q

What are the steps for paper chromatography?

A

Cut a piece of filter paper out(stationary phase), draw line with pencil on paper, place spots of mixture on line, dip paper in the solvent, observe as sample rises up paper and mark where it stops(mobile phase)

22
Q

What is thin-layer chromatography?

A

Process used to separate mixtures of soluble substances

23
Q

What are the steps for TLC chromatography?

A

Cut out piece of a TLC paper(stationary phase), add propane to the substance, draw line of piece of plate with pencil, use a thin capillary tube to add spots of mixture on line, add chromatography solvent into bottle with TLC plate, observe as solvent rises and mark where it stops

24
Q

What is a chromatogram?

A

Result of separating mixtures by chromatography, used to identify substances by comparing them with known substances

25
Q

What is the criteria that suggest substances are the same

A

If they have same number of spots(which must be matching in colour) or if the spots travel same distance as they have Rf value

26
Q

What is the formula to calculate the Rf value

A

distance travelled by substance/distance travelled by solvent

27
Q

What range must the Rf value be between

A

0-1

28
Q

What is the substance not attracted to if its Rf value is 0?

A

Mobile phase

29
Q

What is the substance not attracted to if its Rf value is 1?

A

Stationary phase

29
Q

On a chromatogram, how many pigments does a pure substance have?

A

1

30
Q

On a chromatogram, how many pigments does an impure substance have?

A

2 or more

Chemistry 2 (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions