Answer:
0.500 moles of CO2 has a volume of 11.2 L at STP (option B)
Explanation:
Step 1: Data given
Volume of a gas at STP = 11.2 L
STP: Pressure = 1 atm and temperature = 273 K
Step 2: Calculate volume
p*V= n*R*T
V = (n*R*T)/p
⇒with V = the volume of the gas = TO BE DETERMINED
⇒with n = the number of moles of the gas
⇒with R = the gas constant = 0.08206 L*atm/mol*K
⇒with T = the temperature = 273 K
⇒with p = the pressure of the gas = 1 atm
A
) 0.250 mole of NH3
V = (0.250 * 0.08206 * 273) / 1
V = 5.6 L
B
) 0.500 mole of CO2
V = (0.500 * 0.08206 * 273) / 1
V = 11.2 L
C
) 0.750 mole of NH3
V = (0.750 * 0.08206 * 273) / 1
V = 16.8 L
D) 1.00 mole of CO2
V = (1.00 * 0.08206* 273) / 1
V = 22.4 L
0.500 moles of CO2 has a volume of 11.2 L at STP (option B)
Data:
<span>Solute: 28.5 g of glycerin (C3H8O3)
Solvent: 135 g of water at 343 k.
Vapor pressure of water at 343 k: 233.7 torr.
Quesiton: Vapor pressure of water
Solution:
Raoult's Law: </span><span><span>The vapour
pressure of a solution of a non-volatile solute is equal to the vapour
pressure of the pure solvent at that temperature multiplied by its mole
fraction.
Formula: p = Xsolvent * P pure solvent
X solvent = moles solvent / moles of solution
molar mass of H2O = 2*1.0g/mol + 16.0 g/mol = 18.0 g/mol
moles of solvent = 135 g of water / 18.0 g/mol = 7.50 mol
molar mass of C3H8O3 = 3*12.0 g/mol + 8*1 g/mol + 3*16g/mol = 92 g/mol
moles of solute = 28.5 g / 92.0 g/mol = 0.310 mol
moles of solution = moles of solute + moles of solvent = 7.50mol + 0.310mol = 7.810 mol
Xsolvent = 7.50mol / 7.81mol = 0.960
p = 233.7 torr * 0.960 = 224.4 torr
Answer: 224.4 torr
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