COMEDK2024ChemistryClassification of Elements and Periodicity in Properties
Which of the following statements is/are true about the diagonal relationship of Be and Al ? (i) Both react with NaOH to liberate hydrogen. (ii) Their oxides are basic. (iii) They are made passive by nitric acid. (iv) Their carbides give acetylene on treatment with water.
Options
- AOnly (i)
- B(i) and (iii)
- C(ii) and (iv)
- D(i), (ii), (iii)
Correct answer
B. (i) and (iii)
Step-by-step solution
Statement given in (i) and (iii) are correct, while in (ii) and (iv) are incorrect. BeO and Al ₂ O ₃ are amphoteric. These react with acid as well as alkalines to given corresponding salts. aligned & BeO +2 HCl BeCl ₂+ H ₂ O & BeO +2 NaOH Na ₂ BeO ₂+ H ₂ O & Al ₂ O ₃+6 HCl 2 AlCl ₃+3 H ₂ O & Al ₂ O ₃+2 NaOH 2 NaAlO ₂+ H ₂ O aligned Be ₂ C and Al ₄ C ₃ give methane on treatment with water. aligned & Be ₂ C +4 H ₂ O 2 Be ( OH )₂+ CH ₄ & Al ₄ C ₃+12 H ₂ O 4 Al ( OH )₃+3 CH ₄ aligned