Answer:
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Explanation:
Answer:
P' = 41.4 mmHg → Vapor pressure of solution
Explanation:
ΔP = P° . Xm
ΔP = Vapor pressure of pure solvent (P°) - Vapor pressure of solution (P')
Xm = Mole fraction for solute (Moles of solvent /Total moles)
Firstly we determine the mole fraction of solute.
Moles of solute → Mass . 1 mol / molar mass
20.2 g . 1 mol / 342 g = 0.0590 mol
Moles of solvent → Mass . 1mol / molar mass
60.5 g . 1 mol/ 18 g = 3.36 mol
Total moles = 3.36 mol + 0.0590 mol = 3.419 moles
Xm = 0.0590 mol / 3.419 moles → 0.0172
Let's replace the data in the formula
42.2 mmHg - P' = 42.2 mmHg . 0.0172
P' = - (42.2 mmHg . 0.0172 - 42.2 mmHg)
P' = 41.4 mmHg
Volume ⇒ 50 mL in liters : 50 / 1000 = 0.05 L
Molarity of solution ⇒ 0.15 M
Number of moles:
n = M * V
n = 0.15 * 0.05
n = 0.0075 moles of CuCl2
hope this helps!.
Answer:
9.35g
Explanation:
The molarity equation establishes that:
So, we have information about molarity (2M) and volume (80 ml=0.08 l), with that, we can find the moles of solute:
The mathematical equation that establishes the relationship between molar weight, mass and moles is:
We have MW (58.44g/mole) and n (0.16 mol), and we need to find m (grams of salt needed) to solve the problem:
