Acids and bases

Human blood has a pH between 7.35 and 7.45. Which of the following best describes human blood?

• strongly acidic
• slightly acidic
• strongly basic
• slightly basic

Which of the following statements is correct?

• Blue litmus paper turns red when placed in a base.
• Red litmus paper turns blue when placed in a base.
• Blue litmus paper stays blue when placed in an acid.
• Red litmus paper stays red when placed in a base.

Which is the stronger acid?

• pH 1
• pH 4
• pH 8
• pH 13

Turns litmus blue.

• Acids
• Bases
• Salts
• All

When put into a solution that is basic, phenolphthalein turns __________.

• blue
• violet
• black
• magenta

The indicator that changes basic solution to green is

• Phenolphthalein

• Turmeric

• Methyl Orange

• China rose

An example of acid obtained from mineral is

• Acetic acid

• Tartaric acid

• Nitric acid

• Oxalic acid

An acid present in aerated drinks is

• Carbonic acid

• Lactic acid

• Maleic acid

• formic acid

This acid is used in car batteries and is also called 'Oil of Vitriol'.

• Carbonic acid

• Sulphuric acid

• Nitric acid

• Phosphoric acid

Manure is added when the soil is too

• acidic

• basic

• neutral

• none of these