C1 Unit 2 Revison

Front 1

what does your stomach produce to kill bacteria?

Back 1

hydrochloric acid

Front 2

what does hydrochloric in the stomach prevent?

Back 2

food poisioning

Front 3

how is the food in your stomach broken down?

Back 3

the food is digested (broken down) by digestive enzymes which needs acidic conditions to work properly

Front 4

what happens when your body produces too much acid?

Back 4

indigestion

Front 5

what happens if the acid escapes?

Back 5

the acid will escape from the top of the stomach which causes pain in the tube leading to the mouth which is known as heartburn

Front 6

what can neutralise acids and why?

Back 6

medicines such as antacids neutralise excess acid because they contain bases (substances that reacts with acid)

Front 7

what is the formula for the neutralisation of acids?

Back 7

acid + base (arrow) salt + water

Front 8

what is an alkali?

Back 8

some bases are soluble and a base dissolved in water is an alkali

Front 9

what is the formula if an indigestion tablet reacts with magnesium hydroxide?

Back 9

magnesium hydroxide + hydrochloric acid (Arrow) magnesium chloride + water

Front 10

what is the symbol equation for an indigestion tablet reacting with magnesium hydroxide?

Back 10

Mg(OH)2 + HCL 2 (arrow) 2MgCl2 + 2H2O

Front 11

what is the word and symbol equation if sodium hydroxide reacts with an indigestion tablet?

Back 11

sodium hydroxide + hydrochloric acid (arrow) sodium chloride + water

Na(OH)2 + 2HCL (arrow) NaCl2 + 2H2O

Front 12

what is the word and symbol equation if copper oxide reacts with an indigestion tablet?

Back 12

copper oxide + hydrochloric acid (Arrow) copper chloride + water

CuO + 2HCL2 (arrow) CuCl + 2H20

Front 13

What is the word and symbol equation if potassium hydroxide reacts with sulphuric acid?

Back 13

potassium hydroxide + sulphuric acid ( arrow) potassium sulphate + water

Front 14

what will the reactions of substances reacting with indigestion produce?

Back 14

a colourless solution

Front 15

what two things do we have to observe for the reaction of substances reacting with indigestion tablets?

Back 15

if there is a rise in temperature and if the pH of the reaction mixture changes and you will observe the same things for metal oxides

Front 16

what is produced if an antacid contains carbonate?

Back 16

carbon dioxide will be produced

Front 17

give the word and symbol equation for hydrochloric acid reacting with calcium carbonate?

Back 17

hydrochloric acid + calcium carbonate (Arrow) calcium chloride + water + carbon dioxide

CaCO3 + 2HCl2 (arrow) CaCl2 + H2O + CO2

Front 18

are most metal carbonates soluble?

Back 18

no

Front 19

what do we get when an antacid reacts with carbonates?

Back 19

acid + metal carbonate (arrow) salt + water + carbon dioxide

Front 20

what will you observe when antacids reacts with a carbonate?

Back 20

you will observe bubbles of gas being given off and you can show the gas is carbon dioxide by bubbling it through limewater which turns a cloudy white when it reacts with carbon dioxide

Front 21

if I react calcium carbonate with hydrochloric what will be my three products?

Back 21

calcium chloride + water + carbon dioxide

Front 22

how can we find out is something is an acid or an alkali?

Back 22

we can use an indicator to find out if it is an acid or an alkaline. the pH scale shows colours of the universal indicator. litmus paper is an indicator. the blue litmus paper will turn red under acidic conditions and the red litmus paper will turn blue under alkaline solutions but the litmus paper must be damp.

Front 23

how are dangers shown when associated with substances?

Back 23

we have symbols

Front 24

if an acid or alkali is spilt how can we make this safe?

Back 24

it can be made safe by diluting it with water and by neutralising the acid

Front 25

what are the conditions to neutralise acid?

Back 25

must be a:

- metal oxide

- metal hydroxide

- metal carbonate

Front 26

what is the word equation for neutralising an acid?

Back 26

acid + metal oxide (Arrow) salt + water

Front 27

what is the word equation when neutralising sulphuric with an metal oxide?

Back 27

sulphuric acid + copper oxide (Arrow) copper sulphate and water

Front 28

what is the word equation when neutralising nitric acid with a metal hydroxide?

Back 28

nitric acid + sodium hydroxide (Arrow) sodium nitrate + water

Front 29

what is the word equation when neutralising hydrochloric acid with a metal carbonate?

Back 29

hydrochloric acid + copper carbonate (arrow) copper chloride + water + carbon dioxide

Front 30

what do sulphuric acids produce?

Back 30

sulfate salts

Front 31

what do nitric acids produce?

Back 31

nitrate salts

Front 32

what do hydrochloric acids produce?

Back 32

chloride salts

Front 33

how are compounds decomposed to form new compounds?

Back 33

1. heat - thermal decomposition

2. electricity- electrolysis (compounds are decomposed by electrolysis are called electrolytes)

Front 34

how is chlorine gas produced as an electrode in sea water?

Back 34

sea water contains dissolves substances and the common one is sodium chloride. if a direct current passes through the sea water chlorine gas is produced as one of my electrodes

Front 35

what is the test for chlorine?

Back 35

1. hold damp blue litmus paper at the mouth of the tube in chlorine water

2. if the gas is chlorine the red litmus paper will be bleached into white litmus paper

3. any acidic substance will turn blue litmus paper red

Front 36

what are the uses of chlorine?

Back 36

chlorine is a yellow/green toxic gas but is used in swimming pools to keep the water free from bacteria, this kills microorganisms in the water and is used for cleaning products and for the manufacture of plastics

Front 37

what are the disadvantages of using chlorine?

Back 37

this is harmful to living things but reacts with coloured substances converting them to colourless products and is used in paper making

Front 38

what are the risks of chlorine?

Back 38

- gases can accidentally leak from a chemical factory or a tanker carrying this gas may be involved in an accident

- chlorine is a toxic gas and if it leaks many people can be badly injured or killed

Front 39

how are ionic substances broken down into simper substances?

Back 39

broken down into simpler substances using electrolysis

Front 40

what is formed through electrolysis?

Back 40

metals and gases are formed at the electrodes when an electric current is passed through them

Front 41

describe the process of electrolysis:

Back 41

1. electrolysis breaks down compounds using electrical energy

2. the electricity comes from direct currents eg. battery

3. requires liquid to conduct electricity called the electrolyte

4. electricity is applied to the electrolyte by two electrodes

5.electrolyte contains compounds which are broken down into its components part

6. component parts are released as atoms or molecules often as a gas

Front 42

what do the ionic substances need for electrolysis?

Back 42

the ions must be free to move and ions are only free to move when an ionic substance is dissolved in water or molten (melted)

Front 43

describe the process of electrolysis through the positive and negative ions

Back 43

1. positively charged ions move to the negative electrode during electrolysis and receive electrons and are reduced

2. negatively charged ions move to the positive electrodes during electrolysis so they lose electrons and are oxidised

Front 44

what does the electrolysis of dilute hydrochloric acid produce?

Back 44

produces hydrogen and chlorine gas which can also be produced by the electrolysis of sea water and if a direct current is passed through water, hydrogen and oxygen are given off at the electrodes

Front 45

describe the electrolysis of hydrochloric acid:

Back 45

1. electrolyte is a dilute solution of hydrochloric acid

2. applying a direct current to the electrolyte causes the HCl to decompose into hydrogen and chlorine gas

3. the gases bubble through the solution and can be collected at the electrodes.

Front 46

describe the test for hydrogen

Back 46

1. hold a lighted splint in the mouth of a test tube

2. if the test tube contains hydrogen mixed with air it will explode with a squeaky pop

Front 47

describe the test for oxygen

Back 47

1. light a splint and then blow the flame out

2. end of the light splint should be glowing

3. put the glowing splint in the mouth of the test tube. if the gas is oxygen the glowing splint will then relight

Front 48

describe the test for chlorine

Back 48

chlorine bleaches damp litmus paper turning it red

Front 49

what can hydrogen be used for?

Back 49

used for rocket fuel and pure hydrogen can be obtained from electrolysis but it is flammable

Front 50

what can chlorine be used for?

Back 50

to treat water supplies and kill any microorganisms, manufacture of bleach products, used to make a polymer (PVC), but it is a toxic gas

Front 51

what can oxygen be used for?

Back 51

used for patients in hospitals who need extra oxygen or space crafts carry cylinders of oxygen or make pure oxygen by electrolysis

Front 52

what is sodium hydroxide used for?

Back 52

turns red litmus paper blue but it is corrosive

Front 53

what is brine?

Back 53

a concentrated sodium chloride solution

Front 54

what happens when an electric current passes through brine?

Back 54

if an electric current passes through brine then hydrogen gas forms as the negative electrode and chlorine gas forms as the positive electrode and a solution of sodium hydroxide forms