Question

how much heat is lost when 71.07g of steam at 100 degrees condenses to form liquid water at 100 degrees

Answer 1

Answer:

Q = 160.36[kJ], is the heat lost.

Explanation:

This is a thermodynamic problem where we can find the latent heat of vaporization, at a constant temperature of 100 [°C].

We know that for steam at 100[C], the enthalpy is

$h_{gas} = 2675.6[kJ/kg]$

For liquid water at 100[C], the enthalpy is

$h_{water} = 419.17[kJ/kg]$

Therefore

$h_{g-w} = 2675.6-419.17 = 2256.43[\frac{kJ}{kg} ]$

The amout of heat is given by:

$Q=h_{g-w}*m\\ where:\\m = mass = 0.07107[kg] = 71.01[g]\\Q = heat [kJ]\\Q =2256.43*0.07107\\Q=160.36[kJ]$