Respuesta :
Answer:
a) 4365 kJ
Explanation:
In any thermodynamic system, any heat change is accompanied by the change in temperature. The relation between heat released/gained in a system and the temperature is:
Q=mcΔT
where,
Q is the amount of heat absorbed or released
m is the mass
ΔT is the change in temperature
c is called the specific heat.
Specific heat is defined as heat gained by 1 unit mass of any sample to raise the temperature of the sample by 1 °Celsius.
Thus, from the question:
Mass of aluminum =5 kg
Final temperature = 1000°C
Initial temperature = 30°C
ΔT = (1000 -30)°C = 970°C
Specific heat of aluminum = 900 J/kg°C
Thus, Amount of heat required:
Q = 5 kg×900 J/kg°C×970°C = 4365000 J
The conversion of J into kJ is shown below:
1 J = 10⁻³ kJ
Thus, Heat gained by aluminum =4365000 ×10⁻³ J = 4365 kJ
