Chem

Question 1

Compounds

Answer 1

2 or more substances that are chemically combined, have a fixed ratio and turns in to a new substance so it has new properties

Question 2

Mixtures

Answer 2

2 or more substances that mixed but not chemically combined,they don’t have a fixed ratio and they keep the properties of the induvidual substances

Question 3

What are the 2 substances called in a mixture?

Answer 3

Components

Question 4

Alloys

Answer 4

A mixture of elements and at least on of them is a metal

Question 5

An example of an alloy

Answer 5

Brass - copper and zinc, Bronze - copper and tin, Steel - iron and carbon and sometimes chromium and nickel

Question 6

How is mineral water a mixture?

Answer 6

The minerals are dissolved in it and can be separated. It is also a solution

Question 7

Name different types of ways to separate mixtures.

Answer 7

Sieving, using a magnet, evaporation, filtration, distillation

Question 8

Sieving

Answer 8

When we use a sieve to separate 2 solid components one big and one small. The bigger particles are left on the sieve

Question 9

Using a magnet

Answer 9

When one of the components is magnetic e.g. iron and sulfur

Question 10

Evaporation

Answer 10

When we have a soluble solid dissolved in a liquid so we heat it

Question 11

Filtration

Answer 11

When we have an insoluble solid with a liquid we use a funnel, filter paper, and a beaker. The component left on the filter paper is called a residue and the component in the beaker is called a filtrate

Question 12

Chromatography

Answer 12

a method used to separate mixtures of dissolved chemicals

Question 13

Why do we use chromatography?

Answer 13

To study the dyes used in food and since black has more than one colour, chromatography will work very well

Question 14

Distillation

Answer 14

When we have 2 liquids, we heat the mixture and it goes down then we use a condenser with cold water to condense the hot water and the liquid gets sent to the beaker

Question 15

How can you do paper chromatography?

Answer 15

When we have chromatography paper we make a baseline and draw a dot with black ink. We use a beaker with water not above the black dot and slowly the colours will start to separate

Question 16

Chromatogram

Answer 16

The resulting paper with all of the colurs

Question 17

What are the last colours on the chromatogram?

Answer 17

The primary colours

Question 18

Capillary action

Answer 18

When the chromatography paper has tubes that the water molecules go though and it moves upwards

Question 19

Why do we use black ink?

Answer 19

Because it is a mixture of colours

Question 20

An example of ink that doesn’t dissolve in water

Answer 20

A permanent marker pen needs alcohol to dissolve it

Question 21

Solution

Answer 21

A mixture in which particles (solute) are mixed with particles of a liquid so that the substance can no longer be seen

Question 22

Solute

Answer 22

A substance that is dissolved

Question 23

Solvent

Answer 23

A liquid that substances dissolve in

Question 24

When a solute disappears in a solvent, what is it called?

Answer 24

Dissolving

Question 25

Is a solution a mixture or compound?

Answer 25

A mixture because it can be separated by evaporation

Question 26

Why is milk not a solution?

Answer 26

Because the particles did not completely disappear

Question 27

Conservation of mass

Answer 27

When there is no loss or gain of mass in a solution

Question 28

What is a concentrated solution?

Answer 28

A solution that has more solute particles than solvent and a higher concentration of solute dissolved

Question 29

What is a dilute solution?

Answer 29

A solution that has less solute particles than solvent and a low concentration of solute dissolved

Question 30

Soluble

Answer 30

When a solute can dissolve in a solvent

Question 31

Insoluble

Answer 31

When a solute can't dissolve in a solvent

Question 32

What is a saturated solution?

Answer 32

When we have the maximum amount of solute in a solvent and the solute can be seen at the bottom of the solution

Question 33

What is a unsaturated solution?

Answer 33

When we don't have the maximum amount of solute in a solvent

Question 34

Solubility

Answer 34

The amount of solute that can dissolve in a certain amount (usually 100g) of solvent at a given temperature and pressure to produce a saturated solution

Question 35

What are the factors that affect solubility?

Answer 35

Temperature- The higher the temperature of the solvent, the faster the solute will dissolve Shaking/stirring- Shaking (agitation) cause solids to dissolve faster Particle size- smaller particles dissolve faster because they have more surface area

Question 36

What is something that doesn't increase the rate of dissolving?

Answer 36

Increasing the amount of solute

Question 37

What are variables?

Answer 37

Things that could affect the results of an experiment

Question 38

Independent variable

Answer 38

The variable that you will change

Question 39

Dependent variable

Answer 39

The variable that you will measure

Question 40

Control variable

Answer 40

The variable that you will keep the same

Question 41

Where do the independent and dependent variable go on a graph?

Answer 41

The independent variable- horizontal axis The dependent variable- vertical axis