Ascientist needs to calculate the amount of heat released when a sample of melted iron freezes. which constant should be used?

Hello!

He should use the latent heat of fusion of iron.

Why?

To determine the amount of heat released from the iron when it freezes, the following equation is used:

Where:

Q=Heat released from the iron (kJ)

m=Amount of iron (moles)

L= Latent heat of fusion of iron-Constant (kJ/mol)

The negative sign is because as the iron is freezing, the process is the inverse of melting (fusion).

The latent heat of fusion of iron is 13,8 kJ/mol and this is a constant he needs to amount of heat released when a sample of melted iron freezes.

Have a nice day!

- lead + phosphoric acid = hydrogen + lead(ii) phosphate