Find the molarity of 25g of sodium hydroxide dissolved in 200 mL of water. Identify the solute and solvent in this solution.
Answers
Answer:
Explanation:
Correct option is
B
6.25 m
molality=
kilograms of solvent
moles of solute
moles of NaOH=
Mass of NaOH
Weight of NaOH
=
40
25
=
8
5
=0.625
kilograms of H
2
O=
1000
Weight of H
2
O
=
1000
100
=0.1
∴molality=
kilograms of solvent
moles of solute
=
0.1
0.625
=6.25m
Hence, the correct answer is 6.25.
Explanation:
Given: m = 25 g , V = 0.2 L
Molarity = mass of solute/ molar mass of solute × V
= 25/ 40 × 0.2
= 25/8
= 3.125 mol/L