a) Estimate the energy required for one molecule of water to evaporate.
b) Show that the inter-molecular distance for water is
Answer :
a) According to the question, the latent heat of vaporization for water is given equal to 2268 × 103 J
4.0824 × 107 J is the energy required to evaporate 1 k mol water and the energy required for evaporation of 1 molecule is:
U = 6.8 × 10-20 J
b) Let d represent the distance between the water molecules. Then the volume around one molecule can be written as:
$ \frac{volume(1kmol)}{number\_of\_molecules}=\frac{{{M}_{A}}}{{{N}_{A}}{{\rho }_{w}}}$
Therefore, d3 represents the volume around one molecule
$ {{d}^{3}}=\frac{{{M}_{A}}}{{{N}_{A}}{{\rho }_{w}}}$
Therefore, upon substituting the known values, we get
d = 3.1 × 10-10m