The question is incomplete, the complete question is:
A chemist prepares a solution of vanadium (III) chloride (VCl3) by measuring out 0.40g of VCl3 into a 50.mL volumetric flask and filling to the mark with distilled water. Calculate the molarity of Cl− anions in the chemist's solution. Be sure your answer is rounded to the correct number of significant digits.
Answer:
0.153M of anions
Explanation:
First we calculate the concentration of the solution. From m/M= CV
m=given mass, M= molar mass, C =concentration of solution, V= volume of solution
Molar mass of compound= 51 + 3(35.5)= 157.5gmol-1
0.4g/157.5gmol-1= C×50/1000
C= 2.54×10-3/0.05= 0.051M
But 1 mole of VCl3 contains 3 moles of anions
Therefore, 0.051M will contain 3×0.051M of anions= 0.153M of anions
When you assume that the gas is behaving ideally, the gas molecules are very far from each other that they do not have any intermolecular forces. If it behaves this way, you can assume the ideal gas equation:
PV = nRT, where
P is the pressure
V is the volume
n is the number of moles
R is a gas constant
T is the absolute temperature
When the process goes under constant pressure (and assuming same number of moles),
P/nR = T/V = constant, therefore,
T₁/V₁=T₂/V₂
If V₂ = V₁(1+0.8) = 1.8V₁, then,
T₂/T₁ = 1.8V₁/V₁
Cancelling V₁,
T₂/300=1.8
T₂ =540 K
If you do not assume ideal gas, you use the compressibility factor, z. The gas equation would now become
PV =znRT
However, we cannot solve this because we don't know the value of z₁ and z₂. There will be more unknowns than given so we won't be able to solve the problem. But definitely, the compressibility factor method is more accurate because it does not assume ideality.
