Chemistry Acids and Bases

The range of pH values are 0-6.9 for

• Bases

• Acids

What is the pH of a neutral solution (like pure water)?

• 3

• 5

• 7

• 9

Water has a pH of 7. What is this substance on the pH scale?

• Acid

• Base

• Neutral

• Negative

In water, bases:

• are proton donors

• are proton acceptors

• produce H+

• produce water

In water, acids:

• produces OH-

• accepts H+ from another substance

• are proton donors

• are proton acceptors

The table below names five acid-base indicators and shows the colours seen at various pH values. The pH values of some solutions are: Sulphuric acid pH= 1.0 Carbonic acid pH= 5.5 Ammonia pH= 9.0 Sodium hydroxide pH= 12.0 By using the CODE letters of indicators, answer the following question. Which indicators show the same colour in sodium hydroxide?

• A and B

• B and D

• D and E

• B and C

What is the colour of methyl orange in an acid?

• Red

• Yellow

• Orange

• Colourless

Which of the following pH is strongly acidic?

• 5.0

• 9.5

• 2.0

• 13.4

What is the colour of blue litmus in an acid?

• Pink

• Red

• Purple

• Colourless

When hydrogen ion concentration is greater than hydroxide ion concentration, the solution is

• basic

• acidic

• neutral

• alkaline