Question

How much energy is lost to condense 300. grams of steam at 100.C?

Answer 1

Energy lost to condense = 803.4 kJ

Further explanation

Condensation of steam through 2 stages:

1. phase change(steam to water)

2. cool down(100 to 0 C)

1. phase change(condensation)

Lv==latent heat of vaporization for water=2260 J/g

$\tt Q=300\times 2260=678000~J$

2. cool down

c=specific heat for water=4.18 J/g C

$\tt Q=300\times 4.18\times (100-0)=125400$

Total heat =

$\tt 678000+125400=803400~J$