How much energy in joules is released when 18.5 grams of copper cools from 285 °C
down to 45 °C

1709.4 Joules

Explanation:

The quantity of Heat Energy (Q) released on cooling a heated substance depends on its Mass (M), specific heat capacity (C) and change in temperature (Φ)

Thus, Q = MCΦ

Since Q = ?

M = 18.5 grams

Recall that the specific heat capacity of copper C = 0.385 J/g.C

Φ = 285°C - 45°C = 240°C

Then, Q = MCΦ

Q = 18.5grams x 0.385 J/g.C x 240°C

Q = 1709.4 Joules

Thus, 1709.4 Joules is released when copper is cooled.

c. heat could easily travel through the molecules in the air and escape/enter the flask. removing the air slows down the heat transfer.  

the answer is c i believe