Answer:
1.03mole
Explanation:
Given parameters:
Pressure = 0.884 atm
Temperature = 6°C = 273 + 6 = 279k
Volume = 26.5L
Unknown:
Number of moles = ?
Solution:
To solve this problem, we use the ideal gas equation:
PV = nRT
P is the pressure
V is the volume
n is the number of moles
R is the gas constant = 0.082atmdm³mol⁻¹K⁻¹
T is the temperature
n = =
= 1.03mole
Answer : The freezing point of a solution is
Explanation : Given,
Molal-freezing-point-depression constant =
Mass of urea (solute) = 29.82 g
Mass of solvent = 500 g = 0.500 kg
Molar mass of urea = 60.06 g/mole
Formula used :
where,
= change in freezing point
= freezing point of solution = ?
= freezing point of solvent =
i = Van't Hoff factor = 1 (for urea non-electrolyte)
= freezing point constant =
m = molality
Now put all the given values in this formula, we get
Therefore, the freezing point of a solution is