NCERT Solutions for Class 10 Science Chapter 2 Acids, Bases and Salts
NCERT Intext Questions
Page Number 22
- (a) Hydrochloric acid
- (b) Sulphuric acid
- (c) Nitric acid
- (d) Aqua regia
(ii) Example: Set up the apparatus as shown in the given figure. Take some zinc granules in the test tube. Add about 5 mL dilute hydrochloric acid slowly. Soon the reaction between zinc and hydrochloric acid starts and hydrogen gas is evolved.

Page Number 25
Page Number 28
Page Number 33
Ca(OH)2 + Cl2 → CaOCl2 + H2O
NCERT Exercise Questions
- (a) 1
- (b) 4
- (c) 5
- (d) 10
- (a) NaCl
- (b) HCl
- (c) LiCl
- (d) KCl
- (a) 4 mL
- (b) 8 mL
- (c) 12 mL
- (d) 16 mL
Explanation : HCl + NaOH → NaCl + H2O
From the above reaction 1 mole of HCl is neutrialised by 1 mole of NaOH if 8 ml of HCl is completely neutrilised 10 ml of NaOH then 20 ml of NaOH is neutralized by = $$ \frac{20×8}{10} = \text{16 ml of HCl.}$$
- (a) Antibiotic
- (b) Analgesic
- (c) Antacid
- (d) Antiseptic
- (a) dilute sulphuric acid reacts with zinc granules.
- (b) dilute hydrochloric acid reacts with magnesium ribbon.
- (c) dilute sulphuric acid reacts with aluminium powder.
- (d) dilute hydrochloric acid reacts with iron filings.
Zn (s) + H2SO4 (aq) → ZnSO4 (aq) + H2 (g)
(b) Magnesium ribbon + dil. Hydrochloricacid → Magnesium chloride + Hydrogen gas
Mg (s) + 2 HCl (aq) → MgCl2 (aq) + H2 (g)
(c) Aluminium powder + dil. Sulphuric acid → Aluminium sulphate + Hydrogen gas
2Al (s) + 3H2SO4 (aq) → Al2 (SO4)3 (aq) + 3H2 (g)
(d) Iron filings + Dilute hydrochloric acid → Ferric chloride + Hydrogen gas
2Fe (s) + 6HCl (aq) → 2FeCl3 (aq) + 3H2 (g)
(i) Take solutions of alcohols and glucose.
(ii) Fix two nails on a cork, and place the cork in 100 mL beaker.
(iii) Connect the nails to the two terminals of a 6 volt battery through a bulb and a switch, as shown in the given figure.

(v) The bulb does not glow.
(vi) Repeat the experiment with glucose. The bulb does not glow in this case also.
(vii) This means no ions or H+ ions are present in the solution. This shows that alcohols and glucose are not acidic in nature.
- (a) Neutral
- (b) Strongly alkaline
- (c) Strongly acidic
- (d) Weakly acidic
- (e) Weakly alkaline
- Ans. (a) D
- (b) C
- (c) B
- (d) A
- (e) E
(a) Why does he shift the pH of the fresh milk from 6 to slightly alkaline ?
(b) Why does this milk take a long time to set as curd ?
(b) The alkaline milk takes a longer time to set into curd because the lactic acid being formed has to first neutralise the alkali present in it.
That is why it is always stored in a moisture proof container.
$$\text{(i)} \underset{\text{Sodium hydroxide (Base)}}{NaOH (aq)} + \underset{\text{ Hydrochloric acid (Acid)}}{HCl (aq)} → \underset{\text{Sodium chloride (Salt)}}{NaCl (aq)} +\underset{\text{Water }} {H_2O (l)} \\ \text{(ii)} \space \underset{\text{Acetic acid (Acid)}}{CH_3 COOH (aq)} + \underset{\text{Sodium hydroxide (Base)}}{NaOH (aq)} \rightarrow \underset{\text{Sodium acetate (Salt)}}{CH_3COONa} + \underset{\text{Water}}{H_2O (l)}$$
Uses of washing soda:
(i) Washing soda is used in glass, soap and paper industries.
(ii) It is used for removing permanent hardness of water.
(iii) It is used in the manufacturing of sodium compounds such as borax.
(iv) It is used in fire extinguishers.
Uses of baking soda:
(i) Baking soda is used as an antacid in medicines to remove acidity of the stomach.
(ii) Baking soda is used for making baking powder (used in making cakes, bread, etc.).