Question

0.0387 kg of molten copper at its melting point (1083°C) is poured into a vat of water. How much heat must be removed to cool it to a solid at 22.0°C? (Remember, it has to solidify first.) (Unit=J)

Answer 1

23901.39 J

Step-by-step explanation:

Total Thermal Energy removed

= Energy lost to change state from liquid to solid + Energy lost to cool solid from melting pt to 22 C

= mlf + mcT [bolded is for state change, italicised is for cooling solid from melting pt to 22 C]

= (0.0387)(2.07 × 10^5) + (0.0387)(387)(1083 - 22)

= 23901.39 J (2 dp)