Answer : The molal freezing point depression constant of X is 
Explanation : Given,
Mass of urea (solute) = 5.90 g
Mass of X liquid (solvent) = 450.0 g
Molar mass of urea = 60 g/mole
Formula used :

where,
= change in freezing point
= freezing point of solution = 
= freezing point of liquid X= 
i = Van't Hoff factor = 1 (for non-electrolyte)
= molal freezing point depression constant of X = ?
m = molality
Now put all the given values in this formula, we get
![[0.4-(-0.5)]^oC=1\times k_f\times \frac{5.90g\times 1000}{60g/mol\times 450.0g}](https://tex.z-dn.net/?f=%5B0.4-%28-0.5%29%5D%5EoC%3D1%5Ctimes%20k_f%5Ctimes%20%5Cfrac%7B5.90g%5Ctimes%201000%7D%7B60g%2Fmol%5Ctimes%20450.0g%7D)

Therefore, the molal freezing point depression constant of X is 
Answer:
54.7°C is the new temperature
Explanation:
We combine the Ideal Gases Law equation to solve this.
P . V = n. R. T
As moles the balloon does not change and R is a constant, we can think this relation between the two situations:
P₁ . V₁ / T₁ = P₂ . V₂ / T₂
T° is absolute temperature (T°C + 273)
68.7°C + 273 = 341.7K
(0.987 atm . 564L) / 341.7K = (0.852 atm . 625L) / T₂
1.63 atm.L/K = 532.5 atm.L / T₂
T₂ = 532.5 atm.L / 1.63 K/atm.L → 326.7K
T° in C = T°K - 273 → 326.7K + 273 = 54.7°C
Answer:
1.126 x 10^22
Explanation:
pV = nRT
7.53 x 10 = n x 8.31 x 485
n = (7.53 x 10) / (8.31 x 485) = 0.0187 moles
M = n x Avogadros number
0.0187 x 6.02 x 10^23 = 1.126 x 10^22
Answer:
A. is the correct point.
Explanation:
This is true because no matter how many mL of water is added, the solution only gets more height; the concentration in everything else stays the same, and water doesn't have any concentration. Very confusing, I know. Good luck!
You would have to dig up 261 g of sylvanite.
Mass of sylvanite = 73.0 g Au × (100 g sylvanite/28.0 g Au) = <em>261 g</em> sylvanite.