Acid, Bases, and Salts

Question 1

How to handle explosive chemicals

Answer 1

May explode if handled/ treated incorrectly

Question 2

How to handle flammable chemicals

Answer 2

Chemical ignites easily - Keep away from sparks and flames.

Question 3

How to handle toxic chemicals

Answer 3

Take great care when using

Question 4

Hour to handle corrosive chemicals

Answer 4

Wear glasses + eye protection
Wash off skin

Question 5

How to handle chemicals with caution symbols

Answer 5

Wear glasses+ eye protection
Wash off skin

Question 6

What colour is red litmus paper in acid?

Answer 6

Red

Question 7

What colour is red litmus paper in neutral?

Answer 7

Red

Question 8

What colour is red litmus paper in alkali?

Answer 8

Blue

Question 9

What colour is blue litmus paper in acid?

Answer 9

Red

Question 10

What colour is blue litmus paper in neutral?

Answer 10

Blue

Question 11

What colour is blue litmus paper in alkali?

Answer 11

Blue

Question 12

What colour /number on universal indicator is acidic?

Answer 12

0- 6 ( Red, orange, yellow )
————————————->
Increasing acidity

Question 13

What colour is neutral on the universal indicator and what colour is it?

Answer 13

7 and green

Question 14

What colour /number on universal indicator is alkaline?

Answer 14

8-14 (blue and purple)
——————————>
Increasing alkalinity

Question 15

Advantages of these indicators

Answer 15

• universal indicator and litmus paper are cheap
• ph metre gives exact ph value
• universal indicator gives strength and a rough ph value

Question 16

Disadvantages of these indicators

Answer 16

• PH meters are expensive and can break
• Litmus cannot tell you if it’s strong or weak

Question 17

Describe acids

Answer 17

• Have ph value below 7
• Sour taste, corrosive
• Release hydrogen ions when dissolved in water, which causes acidity

Question 18

Describe the ionisation of strong and weak acids

Answer 18

• Strong acids - completely ionise when dissolved in water to form hydrogen ions ( H+)

• weak acids - partially ionise in water to form hydrogen ions ( H +)

Question 19

Describe alkalis

Answer 19

• PH value above 7
• Caustic, soapy feel
• Release hydroxide ions when dissolved in water, which causes them to be alkaline

Question 20

Describe the ionisation of strong and weak alkalis

Answer 20

• Strong alkalis = completely ionise when dissolved in water to form hydroxide ions ( OH- )

• Weak alkalis = partially ionise when dissolved in water to form hydroxide ions ( OH- )

Question 21

What is a base?

Answer 21

A metal oxide or hydroxide that will neutralise an acid

Question 22

What is an alkali?

Answer 22

A soluble base

Question 23

What is strength?

Answer 23

a measure of how much the acid or alkali ionises when dissolved in water , measured by ph

Question 24

What is concentration?

Answer 24

a measure of how many particles there an dissolved in a certain amount of water, measured in mol dm -3

Question 25

What is neutralisation?

Answer 25

The reaction between the hydrogen ( H +) ions in an acid and the hydroxide (OH-) ions in an alkali to produce water

Question 26

What is a salt?

Answer 26

Compound formed when some / all of the hydrogen ions of an acid and replaced by metal or ammonium ions

Question 27

Reaction of acids with metals

Answer 27

Metal + salt → salt + hydrogen

Question 28

Reactions of acids with bases

Answer 28

Acid + base → salts + water

Question 29

Reactions of acids with metal carbonates

Answer 29

Metal carbonate+acid → salt + Carbon dioxide + water

Question 30

Reactions of acids with metal hydrogen carbonates

Answer 30

Metal hydrogen carbonate + acid → salt + carbon dioxide + water

Question 31

Test for hydrogen gas

Answer 31

Use lit splint for squeaky pop

Question 32

Test for CO2 gas

Answer 32

Bubble into lime water solution ( colourless to cloudy)