NCERT Exemplar Solutions
Class 10 - Science - CHAPTER 2: Acids, Bases and Salts - Long Answer QuestionsQuestion 48
Class 10 - Science - CHAPTER 2: Acids, Bases and Salts - Long Answer Questions
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, \(\mathrm{CH_3COONa}\).
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.