Advertisements
Advertisements
Question
Define an acid.
Advertisements
Solution
An acid is defined as a compound which when dissolved in water produces hydronium ion (H3O+), the only positively charged ion and a negative ion. At first the acid furnishes hydrogen ion (H+) in aqueous solution but this H+ ion combines with a water molecule to form Hydronium ion.
For example : acetic acid, sulphuric acid, nitric acid.
CH3COOH + H2O → H3O+ + CH3COO-
APPEARS IN
RELATED QUESTIONS
When a solution is added to a cloth strip treated with onion extract, then the smell of onion cannot be detected. State whether the given solution contains an acid or a base.
Name the gas evolved when dilute HCl reacts with sodium hydrogencarbonate. How is it recognised?
Why is it wrong to treat a bee sting with vinegar?
What happens when bases react with non-metal oxides? Explain with the help of an example. What does this reaction tell us about the nature of non-metal oxides?
What type of ions are formed?
When a base (or alkali) is dissolved in water.
If iron reacts with dilute sulphuric acid, what will be the products?
Write the balanced equation for the preparation of the following compound (as major product) starting from iron and using only one other substance:
Iron (III) chloride
Fill in the missing data in the following table
| Name of the salt | Formula | Salt obtained from | ||
| Base | Acid | |||
| (i) | Ammonium chloride | NH4Cl | NH4OH | ______ |
| (ii) | Copper sulphate | ______ | ______ | H2SO4 |
| (iii) | Sodium chloride | NaCl | NaOH | ______ |
| (iv) | Magnesium nitrate | Mg(NO3)2 | ______ | HNO3 |
| (v) | Potassium sulphate | K2SO4 | ______ | ______ |
| (vi) |
Calcium nitrate | Ca(NO3)2 | Ca(OH)2 | ______ |
State whether the following statement is true or false. Correct the false statement.
A compound if acidic will turn all indicators red.
Fill in the cross word given in figure with the help of the clues provided.

Across
(2) The solution which does not change the colour of either red or blue litmus.
(4) Phenolphthalein gives pink colour in this type of solution.
(7) Colour of blue litmus in lemon juice.
Down
(1) It is used to test whether a substance is acidic or basic.
(3) It is a natural indicator and gives pink colour in basic solution.
(5) Nature of ant’s sting.
(6) It is responsible for the increase in temperature during a neutralisation reaction.
