Question

Assertion :- One molal aqueous solution of glucose contains 180g of glucose in 1 kg water.
Reason :- Solution containing one mole of solute in 1000g of solvent is called one molal solution.
A. If both assertion and reason are true and the reason is the correct explanation of the assertion.
B. If both assertion and reason are true but reason is not the correct explanation of the assertion.
C. If assertion is true but reason is false.
D. If the assertion and reason both are false.

Answer 1

Correct Answer - A
Molality `=("Number of moles of sollute")/("weight of solvent (in kg)")`
If number of moles of solute = 1
Weight of solvent = 1 kg then, molality = 1, i.e., one molala
For glucose `(C_(6)H_(12)O_(6))` , molecular weight = 180
number of moles `=(180)/(180)=1`, weight of water = 1 kg
Hence, molality of the solution is one.