U4 - Topic One

Question 0

What is the definition of a suspension?

Answer 0

A heterogeneous mixture of a solid in a liquid

Question 1

What is the definition of a solution?

Answer 1

A homogeneous mixture of a solid or gas in a liquid

Question 2

What is the definition of an emulsion?

Answer 2

A heterogeneous mixture of two or more liquids

Question 3

What is the definition of a mist?

Answer 3

Minute droplets of a liquid in a gas

Question 4

What is the definition of a smoke?

Answer 4

Minute droplets of a solid in a gas

Question 5

What is the definition of an alloy?

Answer 5

A mixture of two or more metals or metals and non-metals

Question 6

What is the definition of a gel?

Answer 6

A heterogeneous mixture of a liquid within a solid

Question 7

What is the definition of a meringue?

Answer 7

A heterogeneous mixture of a gas within a solid

Question 8

What is the definition of a foam?

Answer 8

A mass of small bubbles of gas in a liquid

Question 9

What is homogeneous?

Answer 9

A mixture which has uniform composition and properties throughout

Question 10

What is heterogeneous?

Answer 10

A mixture that does not have uniform composition and properties throughout

Question 11

Name three ways you can coma or a compound of two substances and a mixture of the two substances

Answer 11

1) By appearance
2) If it’s magnetic
3) By heat (how it reacts etc)

Question 12

Name three ways you can coma or a compound of two substances and a mixture of the two substances

Answer 12

1) By appearance
2) If it’s magnetic
3) By heat (how it reacts etc)

Question 13

In what state does diffusion take place easiest and why?

Answer 13

Diffusion is faster in gases than it is in liquids and solids, as the molecules are further apart and are moving more quickly

Question 14

What happens to the ink connected to a porous pot when hydrogen is outside the porous pot while air inside it?

Answer 14

The hydrogen diffuses into the pot faster than air diffuses out, causing an increase in pressure in the pot. This extra pressure pushes the ink away from the pot

Question 15

How can you work out if a gas diffuses faster than another gas?

Answer 15

Gases with lower densities diffuse faster than gases with higher densities.

To work out which is lower, you need to work out the Mr (relative molecular mass) by looking at the top-left corner of the elements box in the periodic table and times it by however many atoms there are.

Question 16

If a less dense gas is in a porous pot with a tube dipped in a beaker of water while a more dense gas is outside the pot, what happens to the water?

Answer 16

The gas in the pot would diffuse out of the pot quicker than the second would diffuse into the pot, making a partial vacuum in the porous pot. The water would rise (up the tube) to fill the vacuum

Question 17

What’s Graham’s Law of Diffusion?

Answer 17

The square root of the Mr of one gas divided by the Mr of another

Question 18

What kind of mixtures can be separated using a separating funnel?

Answer 18

Immiscible liquids (liquids which don’t mix together) with different densities

Question 19

What is the process of centrifuging (and then decanting)?

Answer 19

Spinning a mixture of a liquid and insoluble solid very quickly in a test tube so the denser solid is thrown to the bottom of the test tube and the liquid is left on the top. The liquid can then be decanted (poured off) the solid

Question 20

Why is a fluted filter paper more effective than a normal piece of filter paper?

Answer 20

The fluted filter paper has more surface area, so it filters faster

Question 21

What’s the alternative to centrifuging and decanting?

Answer 21

Filtration

Question 22

What precaution should you take when using a solvent that’s highly flammable?

Answer 22

Keep away from Bunsen burners, but if you do need to heat it, use an electric heater or a hot water bath

Question 23

What precaution should you take if you are dealing with something that has harmful vapours?

Answer 23

Put it in the fume cupboard, do the experiment in the fume cupboard

Question 24

What the chemical test for water?

Answer 24

Use anhydrous copper sulfate; it goes from white to blue

Question 25

What’s the solvent and what’s the solute?

Answer 25

The solvent is the substance that something is dissolved into, and the solute is the substance that gets dissolved