Answer:
27) Double replacement
28) 2NaOH + H2SO4 --> Na2SO4 + 2H2O
Sodium-22 remain : 1.13 g
<h3>Further explanation
</h3>
The atomic nucleus can experience decay into 2 particles or more due to the instability of its atomic nucleus.
Usually, radioactive elements have an unstable atomic nucleus.
General formulas used in decay:

T = duration of decay
t 1/2 = half-life
N₀ = the number of initial radioactive atoms
Nt = the number of radioactive atoms left after decaying during T time
half-life = t 1/2=2.6 years
T=15.6 years
No=72.5 g

It would be to change the amount of solute or solvent in the solution.
Weathering is the process of breaking large rocks and boulders into much smaller ones. Weathering can be brought about by wind and water mostly. Sometimes even biological forces account for some types of weathering.