JEE Main20199 Jan 2019Morning ShiftChemistrySolutionsActual
A solution of sodium sulphate contains 92 g of Na + ions per kilogram of water. The molality of Na + ions in that solution in mol kg - 1 is:
Options
- A16
- B4
- C12
- D8
Correct answer
B. 4
Step-by-step solution
Moles of N a + = W e i g h t   o f   N a +   i o n s M o l e c u l a r   w e i g h t = 92 23 = 4 Molality is number of moles of solute present per Kg of Solvent 4 mole of N a + are present in 1 kg of water Hence, molality of N a + ions will be 4