Question

Acidity of diprotic acid in aqueous solution increases in the order:

• A. $H_{2}S<H_{2}Se<H_{2}Te$
• B. $H_{2}Se<H_{2}S<H_{2}Te$
• C. $H_{2}Te<H_{2}S<H_{2}Se$
• D. $H_{2}Se<H_{2}Te<H_{2}S$

Answer 1

The correct option is A $H_{2}S<H_{2}Se<H_{2}Te$

Down the group atomic size of central atom increases. Bond dissociation enthalpy decreases as atomic size increases. So bond dissociation enthalpy decreases as we move down the group. And hence acidity increases in the order $H_{2}S<H_{2}Se<H_{2}Te.$