Question

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

(a) Al³⁺ <Ba²⁺ <Na⁺ (b) Na⁺ <Ba²⁺ <Al³⁺

(c) Ba²⁺ <Na²⁺ <Al³⁺ (d) Al³⁺ <Na⁺<Ba²⁺

Answer 1

Correct option(b) Na⁺ <Ba²⁺ <Al³⁺

Explanation:

According to Hardy Schulze rule, greater the charge on oppositely charged ion, greater is its coagulating power. Since arsenic sulphide is a negatively charged sol, thus, the order of coagulating power is Na⁺ <Ba²⁺ <Al³⁺.