4. (15) Adiabatic reaction heat
We put 20g of solid Al (25 °C) in a bath of liquid Sn (600 °C) to make the Al-Sn alloy with 5
wt. % Al in the electric furnace. Calculate the final temperature in the bath if the process is
adiabatic. The liquid Al-Sn solution is a regular solution with a regular solution parameter (? =
16 kJ/mol).
$C_p(Al, l) = 31.76 \text{ (J K}^{-1} \text{mol}^{-1})$
$C_p(Al, s) = 20.67 + 12.38 \times 10^{-3} T \text{ (J K}^{-1} \text{mol}^{-1})$
$\Delta H^{\circ}_{melting} (Al) = 10.7 \text{ kJ mol}^{-1}, T_{melting} = 660 \text{ °C}$
$C_p(Sn, l) = 28.45 \text{ (J K}^{-1} \text{mol}^{-1})$
Let's assume $C_p(alloy) = X_{Al}C_p(Al) + X_{Sn}C_p(Sn)$
Atomic weight of Al: 26.98 (g mol?¹)
Atomic weight of Sn: 118.71 (g mol?¹)