ce physics of heat

The equation involved in calculating the latent heat L in this experiment is,

Q = mL,
where Q is the amount of heat energy supplied to boil the water
m is the mass of water boiled away

i.e. L = Q/m

In situation (I), water splashed out of the cup because of vigorous boiling. The mass of water escaped from the cup m' is larger than it should be if no splash-out. That is, m' > m
L' = Q/m' < L
The calculated (experimental) result is lower than the actual value of latent heat L.

Situation (II), where water vapour condensed back to the cup. The mass of water escaped m" is less than it should be if no condensation occurred. That is, m'' < m
L" = Q/m" > L
The calculated (experimental) result is larger than the actual value of latent heat.