Latent heat, heat of fusion, heat of vaporization – problems and solutions

1. Calculate the amount of heat added to 1 gram gold to change phase from solid to liquid. The heat of fusion for gold is 64.5 x 103 J/kg.

Known :

Mass (m) = 1 gram = 1 x 10-3 kg

Heat of fusion (LF) = 64.5 x 103 J/kg

Wanted : Heat (Q)

Solution :

Q = m LF

Q = (1 x 10-3 kg)(64.5 x 103 J/kg)

Q = 64.5 Joule

Read :  Parabolic motion, work and kinetic energy, linear momentum, linear and angular motion – problems and solutions

2. Calculate the amount of heat released by 1 gram mercury to change phase from liquid to solid. Heat of fusion for mercury is 11.8 x 103 J/kg.

Known :

Mass (m) = 1 gram = 1 x 10-3 kg

Heat of fusion (LF) = 11.8 x 103 J/kg

Wanted : Heat (Q)

Solution :

Q = m LF

Q = (1 x 10-3 kg)(11.8 x 10

Advertisement
Advertisement
3 J/kg)

Q = 11.8 Joule

3. Determine the amount of heat absorbed by 1 kg water to change phase from liquid to vapor (steam). Heat of vaporization for water = 2256 x 103 J/kg

Known :

Mass (m) = 1 kg

Heat of vaporization (LV) = 2256 x 103 J/kg

Wanted : Heat (Q)

Solution :

Q = m LV

Q = (1 kg)(2256 x 103 J/kg)

Q = 2256 x 10

Advertisement
Advertisement
3 Joule

Read :  Kirchhoff’s first rule – problems and solutions

4. Determine the amount of heat released by nitrogen to change phase from vapor to liquid. Heat of vaporization for nitrogen = 200 x 103 J/kg

Known :

Mass (m) = 1 gram = 1 x 10-3 kg

Heat of vaporization (LV) = 200 x 103 J/kg

Known : Heat (Q)

Solution :

Q = m LV

Q = (1 x 10-3 kg)(200 x 103 J/kg)

Q = 200 Joule

[wpdm_package id=’712′]

  1. Converting temperature scales
  2. Linear expansion
  3. Area expansion
  4. Volume expansion
  5. Heat
  6. Mechanical equivalent of heat
  7. Specific heat and heat capacity
  8. Latent heat, heat of fusion, heat of vaporization
  9. Energy conservation for heat transfer