Acids and Alkalis

Question 1

What is this hazard symbol for?

Two test tubes dripping onto something

Answer 1

Corrisive
Can dissolve other sustances on contact
Causes burns on skin

Question 2

What is this hazard symbol for?

Exclamation mark

Answer 2

Harmful Irritant
May cause skin or eye irritation

Question 3

What is this hazard symbol for?

Skull and crossbones

Answer 3

Toxic
Can cause death if inhaled or ingested

Question 4

Why do we have hazard symbols?

Answer 4

To give a warning about any dangers of chemicals

Question 5

Why are hazard symbols used instead or words?

Answer 5

Univerisally recognisable
Eye catching
Easy to understand

Question 6

What is the PH of a neutral substance

Answer 6

PH 7

Question 7

What is an acid

Answer 7

A substance with a PH less than 7

Question 8

What is an alkali?

Answer 8

A base that is soluble in water. It has a PH more than 7.

Question 9

Give some examples of acids found at home

Answer 9

Orange juice
Lemon juice
Vinegar
Coffee

Question 10

Give some examples of alkalis found at home

Answer 10

Toothpaste
Bleach
Oven cleaner
Soap

Question 11

Give some examples of acids found in the laboratory

Answer 11

Hydrochloric acid
Sulphuric acid
Nitric acid

Question 12

Give some examples of alkalis found in the laboratory

Answer 12

Sodium hydroxide
Potassium hydroxide
Ammonia

Question 13

What is the difference between alkalis and bases?

Answer 13

A base is something that reacts with an acid to form water and a salt.
An alkali is any base that is soluble in water.

Question 14

What is an indicator used for?

Answer 14

To identify an unknown solution as an acid or alkali.

Question 15

What is an indicator?

Answer 15

A dye that changes colour in the presence of an acid or alkali

Question 16

Names some indicators?

Answer 16

Litmus solution
Universal indicator
Red cabbage/beetroot indicator

Question 17

What colour does an universal indicator change to for acids

Answer 17

Red

Question 18

What colour does an universal indicator change to for alkalis

Answer 18

Blue

Question 19

What colour does an universal indicator change to for a neutral solution

Answer 19

Green

Question 20

What happens if you mix an alkaline solution with an equal amount of an acidic solution?

Answer 20

They react to produce a neutral solution

Question 21

What is the reaction called when an acid and alkali produce a neutral solution?

Answer 21

Neutralisation

Question 22

What happens to the PH when an alkali is added to an acid.

Answer 22

The PH is raised.

Question 23

What is produced in neutralisation reactions?

Answer 23

Salt and water.

Question 24

What do all acids contain?

Answer 24

Hydrogen

Question 25

What is Hydrochloric acid?

Answer 25

Hydrogen chloride

Question 26

What is Sulfuric acid?

Answer 26

Hydrogen sulfate

Question 27

What is Nitric acid?

Answer 27

Hydrogen nitrate

Question 28

Describe a neutralisation equation

Answer 28

Reactants on the left, products on the right.

Question 29

What is a base?

Answer 29

Any subtance which neutralises an acid. It has a pH of over 7.

Question 30

Are all bases soluble in water?

Answer 30

No a lot are insoluble in water

Question 31

What is a base that is soluble in water known as?

Answer 31

Alkali

Question 32

What do chemical names for alkalis tend to end in?

Answer 32

Hydroxide

Question 33

What is the chemical name for water?

Answer 33

Hydrogen hydroxide

Question 34

What is the general equation for neutralisation?

Answer 34

Acid + Alkali (or base) ---> Salt + water

Question 35

What is the shape of a neutralisation curve?

Answer 35

Goes gently along bottom/top then steeply rises/falls then gently along the top/bottom

Question 36

Go over neutralisation reaction predictions.