The partial pressure is the amount of linguistic compound there is which makes the lagitude of the element 64.663
Answer:
d. 0.208 M NaOH
Explanation:
M[NaOH] = 23+16+1= 40g/mol
2.40L = 2.4dm3
M=m/Mv
M=20.0g/40g/mol×2.4dm3
M=20.0g ÷ 96
M= 0.208 M NaOH
We will use boiling point formula:
ΔT = i Kb m
when ΔT is the temperature change from the pure solvent's boiling point to the boiling point of the solution = 77.85 °C - 76.5 °C = 1.35
and Kb is the boiling point constant =5.03
and m = molality
i = vant's Hoff factor
so by substitution, we can get the molality:
1.35 = 1 * 5.03 * m
∴ m = 0.27
when molality = moles / mass Kg
0.27 = moles / 0.015Kg
∴ moles = 0.00405 moles
∴ The molar mass = mass / moles
= 2 g / 0.00405 moles
= 493.8 g /mol