Answer:
719.83°C
Step-by-step explanation:
The heat that the sample of Zinc gives is equal to the heat that water is absorbing. That is:
C(Zn) * m(Zn) * ΔT(Zn) = C(H2O) * m(H2O) * ΔT(H2O)
Where:
C is specific heat (Zn: 0.390J/g°C; H2O: 4.184J/g°C)
m is mass (Zn: 2.50g; H2O: 65.0g)
ΔT (Zn: ?; H2O: (22.5°C - 20.0°C = 2.50°C)
Replacing:
0.390J/g°C * 2.50g * ΔT(Zn) = 4.184J/g°C * 65.0g * 2.50
ΔT(Zn) = 697.33°C
As final temperature of Zn is 22.50°C, initial temperature is:
Initial temperature: 697.33°C + 22.50°C
719.83°C