Answer: There are 
atoms present in 0.500 mol of 
.
Explanation:
According to the mole concept, there are 
atoms present in 1 mole of a substance.
In a molecule of there is only one carbon atom present. Therefore, number of carbon atoms present in 0.500 mol of are as follows.
Thus, we can conclude that there are atoms present in 0.500 mol of .
Answer:
Part A. The half-cell B is the cathode and the half-cell A is the anode
Part B. 0.017V
Explanation:
Part A
The electrons must go from the anode to the cathode. At the anode oxidation takes place, and at the cathode a reduction, so the flow of electrons must go from the less concentrated solution to the most one (at oxidation the concentration intends to increase, and at the reduction, the concentration intends to decrease).
So, the half-cell B is the cathode and the half-cell A is the anode.
Part B
By the Nersnt equation:
E°cell = E° - (0.0592/n)*log[anode]/[cathode]
Where n is the number of electrons being changed in the reaction, in this case, n = 2 (Sn goes from S⁺²). Because the half-reactions are the same, the reduction potential of the anode is equal to the cathode, and E° = 0 V.
E°cell = 0 - (0.0592/2)*log(0.23/0.87)
E°cell = 0.017V
Explanation:
The reaction equation will be as follows.
Hence, moles of Na = moles of electron used
Therefore, calculate the number of moles of sodium as follows.
No. of moles = 
= 
(as 1 kg = 1000 g)
= 195.65 mol
As, Q = 
where F = Faraday's constant
= 
= 
mol C
Relation between electrical energy and Q is as follows.
E = 
Hence, putting the given values into the above formula and then calculate the value of electricity as follows.
E =
= 
= 
As 1 J = 
kWh
Hence, 
kWh
= 3.39 kWh
Thus, we can conclude that 3.39 kilowatt-hours of electricity is required in the given situation.
Answer:
The answer should be I and III
Radioactivity another name for radioactive decay. Radioactivity refers to particles emitted from nuclei as a result of nuclear instability.
