Answer is Polonium-218 (84 protons).
alpha decay is an emission of ₂⁴He nucleus. If an element undergoes an alpha decay, the mass of the daughter nucleus formed is reduced by 4 compared to mass of parent atom and atomic number is reduced by 2 compared to atomic number of parent atom.
Since the parent atom has 86 protons, atomic number is 86. Hence, the daughter atom should have 86 - 2 = 84 as atomic number. The parent atom has 222 as its mass. Hence, formed daughter atom should have 222 - 4 = 218 as its mass number.
The reaction for this decay is;
₈₆²²²Rn → ₈₄²¹⁸Po + ₂⁴∝
PH = - log [ H+ ]
pH = - log [ 8.2 x 10⁻⁴]
pH = 3.08
hope this helps!
The answer is- The solubility of a given solute in a given solvent typically depends on temperature.
It’s b . The magnesium will dissolve and the copper will be deposited