NCERT Exemplar Solutions
Class 10 - Science - CHAPTER 2: Acids, Bases and Salts - Long Answer Questions
Question 48

Question. 48

48. Identify the compound X on the basis of the reactions given below. Also, write the name and chemical formulae of A, B and C.

Compound X + Zn → A + H₂(g)

Compound X + HCl → B + H₂O

Compound X + CH₃COOH → C + H₂O

Answer:

X = sodium hydroxide (NaOH).
A = sodium zincate, \(\mathrm{Na_2ZnO_2}\) (formed when Zn reacts with hot concentrated NaOH).
B = sodium chloride (NaCl).
C = sodium acetate, \(\mathrm{CH_3COONa}\).

Detailed Answer with Explanation:

Steps: NaOH reacts with active metals like Zn in hot concentrated alkali to give zincate and H₂: \(\mathrm{Zn + 2NaOH \xrightarrow{\Delta} Na_2ZnO_2 + H_2}\). Reaction with HCl gives salt and water (NaCl + H₂O). Reaction with acetic acid gives sodium acetate and water.

NCERT Exemplar Solutions Class 10 – Science – CHAPTER 2: Acids, Bases and Salts – Long Answer Questions | Detailed Answers