Answer:
0.1 M
Explanation:
Molarity = number of moles / litres of solution.
4 g of calcium bromide = 0.02 mol
(found by dividing 4 g by the atomic mass of CaBr2, which is 199.886)
200 mL of solution = 0.2 litres
Molarity = 0.02 mol / 0.2 L = 0.1 M
Answer:
Standard free-energy change at
is 
Explanation:
Oxidation: 
Reduction: 
--------------------------------------------------------------------------------------
Overall: 
Standard cell potential, 
So, 
We know, standard free energy change at
(
): 
where, n is number of electron exchanged during cell reaction, 1F equal to 96500 C/mol
Here n = 2
So, 
The answer is eight electrons.