How much heat does it take to melt 2.5 kg of lead when it is at its melting point (m. p. = 327.5°c; hf = 2.04 × 104 j/kg)?

6.2 × 10^1 j

8.2 × 103 j

5.1 × 10^4 j

1.7 × 10^7 j

it takes 2.52 × 10^5 j of heat to melt 4.00 kg of a substance. according to the table, what is the substance?

copper

iron

silver

gold

which of the following would you use to calculate the heat released when a liquid freezes?

heat of fuheat of vaporization

heat of condensation

heat of solidification

how much heat is required to completely boil away 0.200 kg of water (hv = 2.26 × 103 kj/kg)?

4.52 × 10^2 kj

2.26 × 10^3 kj

4.52 × 10^3 kj

1.13 × 10^4 kj