Question

What is the maximum mass of ethyl alcohol you could boil with 1000 J of heat, starting from 20C?

Short answer

The answer is$m=1.01\left[g\right]$

Step-by-step solution

Given information

The total heat of ethynyl alcohol is

$Q=Q_1+Q_2$ (1)

The change in temperature as per the equation (19.16) is:

$Q_1=M_c∆T$ (2)

Calculation

M is the mass of ethynyl alcohol

plug the values of $∆TandC$into equation (3) in order to get $Q_1$

$$\begin{gathered} Q_1=M_c(T_2-T_1) \\ =M(2400J/kg.C°)(78°C-20°C) \\ =(1.39\times {10}^{5}J)M \end{gathered}$$

The heat$Q_2$ as a result of phase changes provided in the equation (19.21) is:
$Q_2=M{L}_v$

Thus, plug the value of $L_v$into equation (3) in order to get $Q_2$

$$\begin{gathered} Q_2=M{L}_v \\ =(8.79\times {10}^{5}J/kg)m \end{gathered}$$