IGCSE Combined Sciences: Acids and bases

Match the description to the pH level

a

b

c

d

e

Slightly Acidic

Neutral

Slightly Alkaline

Very Alkaline

Very Acidic

• A

• B

• C

• D

• A

• B

• C

• D

• pH 0

• pH 6

• pH 7

• pH 10

• pH 14

• pH 1

• pH 6

• pH 7

• pH 9

• pH 13

• pH 1

• pH 5

• pH 7

• pH 12

• pH 2

• pH 7

• pH 8

• pH 13

Describe the colour change when excess acid is added to a solution of methyl orange in alkaline solution.

Colour changes from ​ (a)   to ​ (b)  

• Yellow
• Red
• Blue
• Colourless
• Pink
• Orange
• Green
• Black
• White
• Purple

Describe the colour change when excess base is added to a solution of Thylmolphtalein in acidic solution.

Colour changes from ​ (a)   to ​ (b)  

• Yellow
• Red
• Blue
• Colourless
• Pink
• Orange
• Green
• Black
• White
• Purple

Describe the colour of litmus in acidic and alkaline conditions. in acidic conditions litmus is (a)   and in in alkaline conditions Litmus is ​ (b)  

• Blue
• Colourless
• Pink
• Orange
• Green
• Black
• White
• Purple
• Yellow
• Red