S2 exam

Question 1

What are the three names for solutions in water?

Answer 1

Acidic, Alkaline or Neutral

Question 2

What are Indicators?

Answer 2

Indicators tell the difference between acidic, alkaline and neutral solutions they change colour depending on whether they are added to acid or alkaline or neutral solutions.

Question 3

What colour does the universal indicator turn when in acidic solution?

Answer 3

Red

Question 4

What colour does the universal indicator turn when in alkaline solution?

Answer 4

Dark purple/blue

Question 5

What colour does the universal indicator turn when in neutral solution?

Answer 5

Green

Question 6

What is malt vinegar?

Answer 6

Its an acid.

Question 7

How are you able to determine whether a solution is acid, alkaline or neutral?

Answer 7

By which colour it changes to and comparing this to the PH scale.

Question 8

What colours in the PH scale are acid and what are the numbers?

Answer 8

red,orange,yellow,pale green
1,2,3,4,5,6

Question 9

What colours in the PH scale are neutral?

Answer 9

Green
7

Question 10

What colours in the PH scale are alkaline?

Answer 10

Dark green,blue,purple
8,9,10,11,12,13,14

Question 11

What happens when acid and alkali are added together?

Answer 11

They cancel each other out and if the right amount is put in the solution becomes neutral.

Question 12

What is an exothermic reaction?

Answer 12

It means that heat has been given out by the reaction. This is shown by there being an increase in temperature of the products.

Question 13

What does activated charcoal do to the neutral solution?

Answer 13

It removes the colour from the solution

Question 14

What technique is used to separate the activated charcoal from the reaction mixtures?

Answer 14

Filtration

Question 15

What technique is used to remove the soluble product from the water?

Answer 15

Evaporation

Question 16

How are you able to determine the rank of 3 acidic solutions in order of acidity?

Answer 16

Each solution had alkali added to it the more alkali needed the the stronger the acid was.

Question 17

The pain of a wasp sting can be reduced by adding vinegar to the affected area why?

Answer 17

Because the acidity of the vinegar helps neutralize the alkalinity of the sting.

Question 18

Lakes in some parts of the world have lime (alkali) dropped in them why?

Answer 18

Because the lime neutralizes minerals and soil in the water

Question 19

Toothpaste is slightly alkaline why?

Answer 19

To neutralize the acidic conditions in the mouth.

Question 20

Tablets can be taken to reduce the effects of heartburn/ indigestion why?

Answer 20

Because the tablets are antacids and they work by neutralizing the stomach acid which causes heartburn.

Question 21

What is hydrogens reaction?

Answer 21

It burned with a squeaky pop.

Question 22

What is oxygens reaction?

Answer 22

relights a glowing splint.

Question 23

What is carbon dioxides reaction?

Answer 23

turns limewater cloudy.

Question 24

What is filtration?

Answer 24

A substance can only be separated from water by filtration if its insoluble.

Question 25

What is evaporation?

Answer 25

A substance which has dissolved in water can be separated from the water by evaporation.

Question 26

If a mixture of sand and salt was given how would you separate it?

Answer 26

I would add some water to the mixture of sand and salt and stir it. Because it is soluble the salt was able to dissolve in the water. The sand being insoluble was unable to do this so we then filtered the mixture. The sand was unable to pass through the filter paper. The sand being separated left us with the salt water. We separated this by evaporation.

Question 27

How do you measure the calculation of salt in seawater?

Answer 27

e.g-How much salt is in 1L of saltwater? weigh of empty basin= 5.6g weight of empty basin+ salt = 5.8g salt= 0.2g 20cm3x50cm3=1000cm3=1L 0.2x50= 10 There is 10g of salt in 1L of saltwater

Question 28

What is the function of the condenser in a distillation experiment?

Answer 28

To condense the vapours back into a liquid/

Question 29

What is distillation?

Answer 29

Distillation is a method of separating 2 or more liquids with different boiling points.

Question 30

What is chromatography?

Answer 30

Chromatography is separating substances based on their mass. The heavier the pigment the less it travels while the lighter the pigment the more it travels.

Question 31

What are the 3 states of matter?

Answer 31

Solid, liquid, gas

Question 32

What are the states of matter made up of?

Answer 32

Atoms

Question 33

What are the atoms like in the different states of matter?

Answer 33

solid- vibrate in a fixed position liquid- arranged in a random way gas- don't have a fixed shape

Question 34

What state of matter can be compressed?

Answer 34

GAS

Question 35

What is sublimation?

Answer 35

Sublimation is the process by which solids turn into gases without melting into a liquid first eg. solid - gas.

Question 36

What is viscosity?

Answer 36

is a measure of how easily a liquid flows.

Question 37

What state of matter has the quickest diffusion?

Answer 37

GAS

Question 38

What happens when objects get hot?

Answer 38

They expand

Question 39

What happens when objects get cold?

Answer 39

They contract

Question 40

Why don't we get squashed with air pressure?

Answer 40

The pressure inside us pushing out balances the air pressure on the outside pushing in.

Question 41

What is an element?

Answer 41

a substance that is made up from only one type of atom.

Question 42

What is each element given?

Answer 42

A symbol and atomic number

Question 43

What are the 4 groups of elements?

Answer 43

- Alkali metals - Transition metals - Halogens - Noble gases

Question 44

Are noble gases reactive?

Answer 44

NO

Question 45

Are halogens reactive?

Answer 45

VERY YES

Question 46

Alkali metals are group 1 of the periodic table are they reactive

Answer 46

YES (they need to be stored in oil)

Question 47

Are halogens toxic?

Answer 47

YES

Question 48

Can elements that aren't metal conduct electricity?

Answer 48

NO

Question 49

What is a solute?

Answer 49

the substance which dissolves in a solvent.

Question 50

What is a solvent?

Answer 50

is the liquid that dissolves the solute.

Question 51

What is a saturated solution?

Answer 51

A saturated solution is one which can dissolve no more solute into the solvent.

Question 52

What are compounds?

Answer 52

Compounds are formed when atoms of different elements join together.

Question 53

What is a molecule?

Answer 53

A group of atoms joined together

Question 54

When will a compound end in -ide?

Answer 54

If it contains 2 elements

Question 55

When will a compound end in -ite or -ate?

Answer 55

if it contains 3 elements one being oxygen

Question 56

What does Electrolysis mean?

Answer 56

splitting using electricity

Question 57

What gas is essential for combustion?

Answer 57

Oxygen

Question 58

What is catalyst?

Answer 58

speeds up the reaction

Question 59

Pure water can be separated from inky water by simple distillation because

Answer 59

Water evaporates leaving ink particles behind

Question 60

How could you separate iron filings from a mixture of iron and sulphur

Answer 60

Using a magnet sulphur is insoluble

Question 61

For distillation in what part would you expect to find most of the dye at the end of the experiment?

Answer 61

Round bottom flask

Question 62

What is the change of state for melting?

Answer 62

Solid to liquid

Question 63

What is the change of state for boiling?

Answer 63

liquid to gas/ water to steam

Question 64

What is the change of state for condensing?

Answer 64

gas to liquid/ steam to water

Question 65

What is the change of state for freezing?

Answer 65

liquid to solid/ water to ice

Question 66

What is a bi-metallic strip and why does it bend when it is heated?

Answer 66

A strip made up of 2 different metals one expands more than the other