Which one of the following solutions of compounds show highest osmotic pressure? (AB, `AB_2 and A_2B_3` are ionic compounds)

Options

A. 5 . 0 M uear I = 1 . 0 and temperature is `67^(@) C`
B. 1 . 5 M `A_(2)B_(2)` type I = 4 . 1 and temperature is `27^(@) C`
C. 3 . 0 M AB type I = 1 . 6 and temperatue is `27^(@) C`
D. 2 . 5 M `AB_(2)` type I = 2 . 5 and temperatuer is `57^(@)C`

Answer

D

Explanation

`:. pi ` = ic Rt. Thus
(a) ` pi ` for 5 . 0 M urea is
` pi = 1 xx 5 xx R xx 340 (T = 67 + 273)`
`pi = 1700 R`
(b) `pi for 1 . 5 M A_(2) B_(3)` type is (i = 4)
`pi = 4 . 1 xx 15 xx R xx 300 (T = 27 + 273)`
`pi = 1800 R . (~~ 1845)`
(c) `pi` for 3 . 0 M AB type is (i=16)
`pi = 1.6 xx 3 xx R xx 300 (T = 27 + 273)`
`pi = 1440` R
(d) `pi` for `2 . 5 M AB_(2)` type is (i = 25)
`pi = 2. 5 xx 2.5 xx R xx 330 (T = 57 + 273)`
`pi = 2062.5` R
Hence, highest osmotic pressure we get in sample (d)