Question

17. How many grams of KCI must be added to
75.0 grams of water to produce a solution that is
2.25 molal (m)? [Molecular weight of KCl = 74.5]
(1) 126 g
(2) 63 g
(3) 45 g
(4) 12.57 g​

Answer 1

# GIVEN

W1 = 75 g = 0.075 kg

M1 = 18 g/mol

W2 = ?

M2 = 74.5 g/mol

m = 2.25 mol

# SOLUTION:-

Molality of solution is calculated by -

Molality = moles of solute / mass of solvent

m = n2 / W1

m = (W2/M2) / W1

W2 = m × M2 × W1

W2 = 2.25 × 74.5 × 0.075

W2 = 12.57 g

Therefore, 12.57 g of KCl must be added to 75 gram of water to produce a solution that is 2.25 molal.

HOPE IT HELPS TO UU..

Answer 2

Answer:

here is ur answer

hope this is helpful