Question

How much heat is absorbed when 52.3 g `H_2O`(l) at 100 C and 101.3 kPa is converted to steam at 100 C? The molar heat of vaporization of water is 40.7 kJ/mol.

Answer 1

Approx. `+100*kJ`................

Explanation:

We assess the energy transfer involved in the reaction......

`H_2O(l) +DeltararrH_2O(g)`

Both the water and the steam are `100` `""^@C` in temperature.

We are given that `DeltaH_"vaporization"=40.7*kJ*mol^-1`.

And thus `Delta=(52.3*g)/(18.01*g*mol^-1)xx40.7*kJ*mol^-1=??kJ`

How would we change the answer if we were asked to assess the energy transfer when the same quantity of steam CONDENSED to give water at `100` `""^@C`?