Question

The specific heat of gold is 0.126 J/g°C. What mass of gold would change its temperature from 25.0 °C to 60.0 °C with the addition of 2825 J of heat energy? a 570 g b 641 g c 540 g d 610 g

Answer 1

Answer:

The correct answer is option B,  641 g

Explanation:

Answer 2

The amount of heat energy needed to increase the temperature of a substance by $\Delta T$ is given by:
$Q=m C_s \Delta T$
where m is the mass of the substance, Cs is its specific heat capacity and $\Delta T$ is the increase in temperature of the substance.

In this problem, we have a certain mass m of gold, with specific heat capacity $C_s=0.126 J/g^{\circ}C$, to which we add Q=2825 J of energy. Its temperature increases by $\Delta T=60-25=35 ^{\circ}C$. Therefore, if we re-arrange the previous equation, we can find the mass of the block of gold:
$m= \frac{Q}{C_s \Delta T} = \frac{2825J}{0.126\cdot 35}} =641 g$
So, the correct answer is B.