Discussion Forum



1)

The coagulating power of electrolytes having  ions Na+, Al3+   and Ba2+  for arsenic  sulphide  sol increases in the order

 


A) $Al^{3+}$ < $Ba^{2+}$ < $Na^{+}$

B) $Na^{+}$ < $Ba^{2+}$ < $Al^{3+}$

C) $Ba^{2+}$ < $Na.^{2+}$ < $Al^{3+}$

D) $Al^{3+}$ < $Na^{+}$ < $Ba^{2+}$

Answer:

Option B

Explanation:

According to HARDY SCHULZE RULE, the greater the charge on the oppositely charged ion, greater is its coagulating power. Since arsenic sulphide is a negatively charged sol, thus , the order of coagulating power is 

$Na^{+}$  <  $Ba^{2+}$   <  $Al^{3+}$