Question

An aluminum engine block requires 8669 kJ of energy for the temperature to rise from 75.0 °F to 195 °F. The specific heat of lead is 0.897 J/(g°C)( What is the mass of the engine in kg? Please note that the temperatures are in °F, and need to be converted to °C.

Answer 1

Answer:

The answer to your question is 144 kg

Explanation:

Data

Q = 8669 kJ

T1 = 75°F

T2 = 195°F

Cp = 0.897 J/(g°C)

m = ?

Formula

           Q = mCp(T2 - T1)

Process

1.- Convert temperature to °C

T1 = (75 - 32) / 1.8

   = 43/1.8

   = 23.9°C

T2 = (195 - 32) / 1.8

     = 163/1.8

     = 90.6°C

2.- Solve for m

            m = Q / Cp(T2 - T1)

3.- Substitution

            m = 8669000 / 0.897(90.6 - 23.9)

4.- Simplification

            m = 8669000 / 59.83

5.- Result

            m = 144893.66 g or 144.9 kg