Answer: 4. and
Explanation:
a) The given reaction is
As the mass on both reactant and product side must be equal:
As the atomic number on both reactant and product side must be equal:
b)
Total mass on reactant side = total mass on product side
15 =15 + x
x = 0
Total atomic number on reactant side = total atomic number on product side
8 = 7 + y
y = 1