The final temperature is -138 °C.
Explanation:
Using the equation of specific heat
We can easily find the final temperature of a 73.174 g of copper sample. As we know that specific heat is the amount of energy required to raise the temperature of the object to 1°C.
The specific heat of copper is known as 0.387 J/g°C and the initial temperature is said as 102 °C . The mass is given as 73.174 g. The heat released is 6800 J.
Since the heat is released the Q value will be negative.
Thus, the final temperature is -138 °C.
Rubidium Chromate is the compound
Answer:
669.48 kJ
Explanation:
According to the question, we are required to determine the heat change involved.
We know that, heat change is given by the formula;
Heat change = Mass × change in temperature × Specific heat
In this case;
Change in temperature = Final temp - initial temp
= 99.7°C - 20°C
= 79.7° C
Mass of water is 2000 g ( 2000 mL × 1 g/mL)
Specific heat of water is 4.2 J/g°C
Therefore;
Heat change = 2000 g × 79.7 °C × 4.2 J/g°C
= 669,480 joules
But, 1 kJ = 1000 J
Therefore, heat change is 669.48 kJ
