How much water can be heated from
15 C to boiling with
a gas burner with an
efficiency of 35% by
burning 100 l of
natural gas?

The mass is  

Explanation:

From the question we are told that

     The initial temperature is  

      The final  temperature is  

Generally the maximum heat produced by  1  Liter   of  natural gas is  

 So the amount of heat produced by 100 L is  

=>          

Generally given that the efficiency is  

Then actual heat received by the water is

=>

=>

Converting to kcal  

=>

Generally the specific heat of water is  

Generally the heat received by the water is mathematically represented as

=>    

=>    

electrical power