<u>Answer:</u> The freezing point of solution is -0.454°C
<u>Explanation:</u>
Depression in freezing point is defined as the difference in the freezing point of pure solution and freezing point of solution.
The equation used to calculate depression in freezing point follows:

To calculate the depression in freezing point, we use the equation:

Or,

where,
Freezing point of pure solution = 0°C
i = Vant hoff factor = 2
= molal freezing point elevation constant = 1.86°C/m
= Given mass of solute (KCl) = 5.0 g
= Molar mass of solute (KCl) = 74.55 g/mol
= Mass of solvent (water) = 550.0 g
Putting values in above equation, we get:

Hence, the freezing point of solution is -0.454°C
Answer: 300 K
Explanation:
Charles' Law: This law states that volume is directly proportional to the temperature of the gas at constant pressure and number of moles.
(At constant pressure and number of moles)

Given : V= 6.0 L
k= 0.020 L/K
T=?


Thus temperature of the gas is 300 K.
Answer:
0.3793 M
Explanation:
The unknown metal is zinc. So the equation of the reaction is;
Zn(s) + Cu^2+(aq) -------> Zn^2+(aq) + Cu(s)
From Nernst equation;
E = E° - 0.0592/n log Q
[Cu2+] = 0.050179 M
n = 2
[Zn^2+] = ?
E = 1.074 V
E° = 0.34 - (-0.76) = 1.1 V
Substituting values;
1.074 = 1.1 - 0.0592/2 log [Zn^2+]/0.050179
1.074 - 1.1 = - 0.0592/2 log [Zn^2+]/0.050179
-0.026 = -0.0296 log [Zn^2+]/0.050179
-0.026/-0.0296 = log [Zn^2+]/0.050179
0.8784 =log [Zn^2+]/0.050179
Antilog(0.8784) = [Zn^2+]/0.050179
7.558 = [Zn^2+]/0.050179
[Zn^2+] = 7.558 * 0.050179
[Zn^2+] = 0.3793 M