Answer : The 
for this reaction is, -88780 J/mole.
Solution :
The balanced cell reaction will be,
Here, magnesium (Cu) undergoes oxidation by loss of electrons, thus act as anode. silver (Ag) undergoes reduction by gain of electrons and thus act as cathode.
The half oxidation-reduction reaction will be :
Oxidation : 
Reduction : 
Now we have to calculate the Gibbs free energy.
Formula used :
where,
= Gibbs free energy = ?
n = number of electrons to balance the reaction = 2
F = Faraday constant = 96500 C/mole
= standard e.m.f of cell = 0.46 V
Now put all the given values in this formula, we get the Gibbs free energy.
Therefore, the for this reaction is, -88780 J/mole.
Answer:
Mass, temperature, and phase.
I think temperature because the higher the temperature of a given quantity of a substance, more is its thermal energy. Similarly, for the same temperature, higher mass of a substance will contain more thermal energy.
The metal is sodium, Na.
<u>Explanation:</u>
K₂O is an ionic compound in which K is in the oxidation state of +1 and it belongs to group 1.
Group 1 elements also form oxides with the metals with the general formula M₂O and M being Na, K, Li and so on.
Metals Like sodium and Potassium are so brittle in nature and also their oxides.
So the other metal that form metal oxide which is brittle as well as ionic in nature, and so the metal oxide is Na₂O.
So the metal is sodium, Na.
Only answers C and D would make sense in this question. Hope I helped please give brainiest!
