Unstable, radioactive atom emits alpha and gamma ray to transform into a stable atom.
Emitting an alpha particle, decreases the mass number by four and atomic number by two.
Emitting gamma ray reduces the excess energy of the radioactive atom.
I think it’s 20 mol
Sorry if I’m wrong
The redox reaction is

Here
Calcium undergoes reduction, and acts as cathode
Lithium undergoes oxidation and acts as anode
The reduction potential of calcium is -2.87 V
The reduction potential of lithium is - -3.05 V
We know that
Ecell = Ecathode - Eanode
Ecell = -2.87 - (-3.05) = 0.18 V
1st one= CaO +H2O=Ca(OH)2
product side-
Ca=1
O=2
H=2
Reactant side-
Ca=1
O=2
H=2
The first one is balanced for you
There is 1 calcium on each side 2 oxygens on each side and 2 hydrogens on each side