Answer to Question #118886 in General Chemistry for S. Anton

Question

2. What is the change in temperature of aluminum when a 245 g piece of hot aluminum is dropped into a bin of 87.0 g of water at 2.7 °C and the resulting temperature is 35 °C. (caluminum = 0.900 J/g°C)

Answer 1

The heat that aluminum transfers to the water heats the water up from its initial to final temperature:

$$c_\text{Al}m_\text{Al}\Delta t_\text{Al}=c_\text{w}m_\text{w}(t_\text{w f}-t_\text{w i}),\\ \space\\ \Delta t_\text{Al}=\frac{c_\text{w}m_\text{w}(t_\text{w f}-t_\text{w i})}{c_\text{Al}m_\text{Al}}=\frac{4.2\cdot 87(35-2.7)}{0.9\cdot245}=13.3^\circ\text{C}.$$