[A-level]Latent Heat Question, Help

[Boogeyman]

Homework Statement

The specific latent heat of vaporization of water at 28\circC is 2.3 x 10⁶JKg^-1. It has been estimated that 1.2 x 10¹² m³ of water is evaporated per day from the Earth's surface.

Given that the density of water is 1 x 10³ kgm^-3calculate the energy required to evaporate this volume of water.

The Attempt at a Solution

I'm thinking since the water is just evaporating and not boiling, the energy needed would be the heat required to just evaporate the water:

E_H=m_water x latent heat
=2.67 x 10¹⁸J

But this is wrong. I realize I have not used the density of water but I do not know how to apply it. Is this question asking me to find the increase in internal energy?

In any case the volume of water is 1.02 x 10⁹m³.

 

[rock.freak667]

E_H=m_water x latent heat

What did you use for the mass of water? You need to find the mass using m_water=ρV

 

[Boogeyman]

What did you use for the mass of water? You need to find the mass using m_water=ρV

I cannot believe I made such a silly mistake. For some reason I always saw the volume as the mass.

Anyways I got the correct answer now. Thanks.