An insulated beaker contains 300g of water initially at 30 degree celsius. water at 100 degree celsius is added until the temperature of mixture reaches 50 degree celsius . the specific heat capacity of water is 4.2J/(kg degree celsius). how much water is added?

3 answers

.3 (50-30)(4.2) - m (100-50)(4.4)

.3(20)-m(50)

m = .12 kg = 120 g
where did (3) come from?
300 g converted to kg
300/1000 =.3kg