S 1.1

Question 1

Classify matter

Answer 1

All matter
-Pure Substances: Elements, Compounds
-Mixtures: Heterogeneous, Homogeneous

Question 2

What are elements?

Answer 2

Pure substances that cannot be broken down into simpler substances.

Question 3

What are compounds?

Answer 3

Atoms of different elements chemically bonded together in a fixed ratio.

Question 4

What changes between compounds and elements

Answer 4

Their physical properties are completely different for those of their component elements.

Question 5

What is a chemical formula?

Answer 5

Combination of symbols of its elements with a subscript that is used to show the number of atoms of each element in a unit of the compound.

Question 6

What is a homogeneous mixture

Answer 6

The inter particle attraction within the different components must be similar in nature to those between the components in the mixture

Question 7

What is a heterogeneous mixture?

Answer 7

Non-uniform composition. Properties are not the same throughout.

Question 8

How can different components in a mixture be separated (because of what)

Answer 8

If they have distinct physical properties.

Question 9

Explain the process of filtration

Answer 9

Solid is separated from a liquid or gas using a membrane. The solid is collected on the membrane as the residue and the filtrate with the solution passes through.

Question 10

Explain the process of evaporation

Answer 10

Water can be separated by a salt by evaporation, which allows the salt crystals to crystallize.

Question 11

Explain the process of distillation

Answer 11

Separate solvent from solute. Solvent has a lower boiling point than the solute, so that it is collected as a gas and passes into the condensing tube which is surrounded by cold flowing water. Gas is condensed into the pure solvent collected in the beaker at the bottom.

Question 12

Explain the process of paper chromatography

Answer 12

Small spots of solutions containing the samples being tested are placed on the baseline. The paper is suspended to ensure that it is saturated. Different components have different affinities for the water in the paper and so separates as the solvent moves up the paper.

Question 13

What are states of matter

Answer 13

Matter exists in different states as determined by the temperature and the pressure

Question 14

The kinetic molecular theory-Solids

Answer 14

Particles are closely packed together
-Inter particle forces are strong, vibrate in position
-Fixed shape
-Fixed volume

Question 15

The kinetic molecular theory- Liquids

Answer 15

-Particles are more spaced
-Inter particle forces are weaker, particles can slide over eachother
-No fixed shape
-No fixed volume

Question 16

The kinetic molecular theory- Gas

Answer 16

-Particles fully spread out
-Inter particle forces are weak, move freely
-No fixed shape
-No fixed volume.

Question 17

What is the temperature of a system related to?

Answer 17

The average kinetic energy of the particles and the state of matter at a given temperature.

Question 18

What is the pressure of a system related to?

Answer 18

Strength of inter-particle forces that exist between particles.

Question 19

Explain the boiling process

Answer 19

-Boiling point is the temperature at which the vapour is equal to the external pressure
-Liquid is heated, more particles enter the vapour state and the pressure increases
-When the vapour pressure reaches the external atmosphere pressure it boils
-When the external pressure is lower than the vapour pressure, it is reduced and boiling point occurs at a lower temperature.

Question 20

Explain state changing

Answer 20

Vibrations are sufficiently energetic for the particles to move away from their fixed positions and form whatever. Energy added during this stage is used to break the inter particle forces, not to raise the kinetic energy so the temperature remains constant.

Question 21

How to transform from celcius to kelvin

Answer 21

+273º

Question 22

Where is the total kinetic energy conserved in?

Answer 22

The collisions.

Question 23

How do you calculate the Rf value?

Answer 23

distance moved by component/distance moved by solvent