Question

$A s _ { 2 } S _ { 3 }$ sol has a negative charge. Capacity to precipitate it is highest in .

• A. $\mathrm { AlCl } _ { 3 }$
• B. $\mathrm { Na } _ { 3 } \mathrm { PO } _ { 4 }$
• C. $\mathrm { CaCl } _ { 2 }$
• D.

Answer 1

Answer: (A)

$\mathrm { AlCl } _ { 3 }$

Answer 2

Sol Negatively charged $A s _ { 2 } S _ { 3 }$sol coagulated most effectively by$\mathrm { AlCl } _ { 3 }$. This is because oppositely charged $A l ^ { + + + }$ ions have maximum charge.

$\mathrm { As } ^ { 3 + } > \mathrm { Ca } ^ { 2 + } > \mathrm { Na } ^ { + }$