Answer:
Solid magnesium chloride is a non-conductor of electricity because the ions aren't free to move. However, it undergoes electrolysis when the ions become free on melting. Magnesium chloride dissolves in water to give a faintly acidic solution (pH = or 6).
Answer:
The student's conclusion is not correct
Explanation:
Activation energy is the minimum amount of energy required for a reaction to occur. All reactions require there activation energy to be met before the reaction can proceed. When the temperature of a reaction is increased, the kinetic energy of the reactant molecules increases; colliding more with each other, which makes them "surmount" the activation energy of the reaction faster as compared to a lower temperature.
In combustion, there is burning of an hydrocarbon (in this case propane) in excess oxygen. The burning assists in increasing the kinetic energy of the reactant particles which in turn easily surmounts the activation energy of the reaction by colliding (effective collision) more with oxygen. So, the reaction has an activation energy but the activation energy has been met and passed and hence the reaction is proceeding faster.
Increasing the temperature of a reaction is one of the ways of increasing the rate of a chemical reaction.
Answer:
ΔG = -61.5 kJ/mol (<u>Spontaneous process</u>)
Explanation:
2 NO (g) + O₂ (g) ⇄ 2NO₂ (g)
Let's apply the thermodynamic formula to calculate the ΔG
ΔG = ΔG° + R .T . lnQ
We don't know if the gases are at equilibrium, that's why we apply Q (reaction quotient)
ΔG = - 69 kJ/mol + 8.31x10⁻³ kJ/K.mol . 298K . ln Q
How can we know Q? By the partial pressures (Qp)
P NO = 0.450atm
PO₂ = 0.1 atm
PNO₂ = 0.650 atm
Qp = [NO₂]² / [NO]² . [O₂]
Qp = 0.650² / 0.450² . 0.1 = 20.86
ΔG = - 69 kJ/mol + 8.31x10⁻³ kJ/K.mol . 298K . ln 20.86
ΔG = -61.5 kJ/mol (<u>Spontaneous process</u>)
Cu + S ---> CuS
by reaction 1 mol 1 mol
from the problem 0.25 mol 0.25 mol
0.25 mol Cu
