AP EAMCET2011ChemistrySolutions
Which one of the following is the ratio of the lowering of vapour pressure of 0.1 M aqueous solutions of BaCl ₂, NaCl and Al ₂ ( SO ₄ )₃ respectively?
Options
- A3 : 2 : 5
- B5 : 2 : 3
- C5 : 3 : 2
- D2 : 3 : 5
Correct answer
A. 3 : 2 : 5
Step-by-step solution
Lowering of vapour pressure is a colligative property. It depends on the number of particles of the solute. aligned BaCl ₂ & Ba ²⁺+2 Cl ⁻ ; 3 ions NaCl & Na ⁺+ Cl ⁻ ; 2 ions Al ₂ ( SO ₄ )₃ & 2 Al ³⁺+3 SO ₄³⁻ ; 5 ions aligned Hence the ratio of lowering of vapour pressure is 3: 2: 5 .