Question

Type the correct answer in each box. Express your answer to four significant figures. The temperature of 15.71 grams of gold rises from 32°C to 1,064°C, and then the gold melts completely. If gold’s specific heat is 0.1291 joules/gram degree Celsius and its heat of fusion is 63.5 joules/gram, how much energy is gained by the gold? The gold gained a total of _____ joules of energy.

Answer 1

Answer:- 3091 J.

Solution:- Mass of gold is 15.71 g and it's temperature is changing from 32 degree C to 1064 degree C. 1064 degree C is also the melting point of gold.

This process takes place in two steps. In first step, 32 degree C gold changes to 1064 degree gold and then in next step the phase change takes place where solid gold changes to liquid gold.

For the first step, we use the formula, $q=mc\Delta T$

$\Delta T$ = 1064 - 32 = 1032 degree C

Let's plug in the values in the formula:

$q=15.71g(\frac{0.1291J}{g.^0C})(1032^0C)$

q = 2093 J

For second step, the formula is, $q=m\Delta H_f_u_s$

where $\Delta H_f_u_s$ is enthalpy of fusion.

Let's plug in the values:

$q=15.71g(\frac{63.5J}{g})$

q = 998 J

Total heat gained by gold = 2093 J + 998 J = 3091 J

So, gold gained a total of 3091 J of energy.

Answer 2

Answer:

3091

Explanation:

I got it right on the test