Question

the mass of steam at hundred degree centigrade is to be passed into water of mass hundred grams at 20 degree centigrade to raise its temperature by 5 degrees centigrade is (a)0.4g (b)0.8g ​

Answer 1

The mass of steam : 0.8 g

Explanation:

To find the quantity of heat required to raise the temperature by 5 degree

Q = m c Δθ

here m is the mass of water , c is its specific heat and Δθ is the rise in temperature

Here m = 100 gm ,  c = 1 cal  , Δθ = 5 degree

Thus Q = 100 x 1 x 5 = 500 cal

When the steam is made to pass through water , it condenses to water and heat is released . In this case , there is no change in temperature

Thus Q = m L  , here L is the latent heat of steam and m is the mass

Thus m = Q/L = 500/542 = 0.8 g approx

Here 542 cal  is the latent heat of vaporization for water

Answer 2

Answer:

the above answer is perfectly correct