alleryStart learning →A 3.00 kg sample at its boiling point is entirely boiled away by 5360 kJ of heat. What is this substance's latent heat of vaporization?
A895 kJ/kg
B1340 kJ/kg
C1790 kJ/kg
D3580 kJ/kg
Answer & Solution
Correct answer: C. 1790 kJ/kg
1. Rearranging Q = mLv for the latent heat of vaporization gives Lv = Q divided by m.
2. Substitute Q = 5360 kJ and m = 3.00 kg.
3. Dividing gives Lv = 1786.7 kJ/kg, which rounds to 1790 kJ/kg.
4. 895 kJ/kg is half this value, and 3580 kJ/kg is double it.
5. 1340 kJ/kg does not match this division at all.
6. So 1790 kJ/kg is correct.
_Source: OpenStax Physics (CC BY 4.0), Ch 11 "Thermal Energy, Heat, and Work", section 11.3 Phase Change and Latent Heat_
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