(a)[2]
Define what is meant by specific latent heat.
(b)
A beaker with a liquid is placed on a balance, as shown in Fig. 3.1. An immersed heater with power $110\,\text{W}$ is placed in the liquid. The heater is switched on and, once the liquid is boiling, balance readings $m$ are recorded at matching times $t$. Figure 3.2 shows how the balance reading $m$ varies with time $t$.
(b(i))[1]
State the feature in Fig. 3.2 that indicates the liquid is boiling at a steady rate.
(b(ii))[3]
Use the data from Fig. 3.2 to find a value for the specific latent heat $L$ of vaporisation of the liquid.
(b(iii))[2]
State, with a reason, whether the value found in (ii) is more likely to be an overestimate or an underestimate of the accepted specific latent heat of vaporisation of the liquid.