An 1% solution of KCl (I), NaCl (II), BaCl2 (III) and urea (IV) have their osmotic pressure at the same temperature in the ascending order (molar masses of NaCl,KCl,BaCl2 and urea are respectively 58.5, 74.5, 208.4 and 60 g. mol-1) .Assume 100 % ionization of the electrolytes at this temperature

Question

An 1% solution of KCl (I), NaCl (II), BaCl2 (III) and urea (IV) have their osmotic pressure at the same temperature in the ascending order (molar masses of NaCl,KCl,BaCl2 and urea are respectively 58.5, 74.5, 208.4 and 60 g. mol-1) .Assume 100 % ionization of the electrolytes at this temperature (A)  I < III < II < IV  (B)  III < I < II < IV  (C)  I < II < III < IV  (D)  I < III < IV < II

Tardigrade Admin · Accepted Answer

1% solution means 1 g solute is present in 100 mL of water. Osmotic pressure,

π = \frac{i w \times RT}{M \times V}

∴

π_{K Cl} = \frac{2 \times 1 \times 1000 \times RT}{74.5 \times 100}

= 2 \times 0.134 RT

π_{N a Cl} = \frac{2 \times 1 \times 1000 \times RT}{58.5 \times 100}

= 2 \times 0.171 RT

π_{B a C l_{2}} = \frac{3 \times 1 \times 1000 \times RT}{208.4 \times 100}

= 3 \times 0.048 RT

π_{u re a} = \frac{1 \times 1 \times 1000 \times RT}{60 \times 100}

= 1 \times 0.167 RT

Since, temperature is same in all cases, the ascending order of osmotic pressure is

III < I V < I < II

$I < III < II < I V$

$III < I < II < I V$

$I < II < III < I V$

$I < III < I V < II$

$III < I V < I < II$

I<III<II<IV

III<I<II<IV

I<II<III<IV

I<III<IV<II

III<IV<I<II

$I < III < II < I V$

$III < I < II < I V$

$I < II < III < I V$

$I < III < I V < II$

$III < I V < I < II$