Question

Some milk at 10.2 C is added to 231 g of milk at 86.9 C. The final temperature of the mixture is 72.4 C. What mass of cold milk was used?

Answer 1

53.85 g

Step-by-step explanation:

Given:

T₁ = 10.2°C

m₂ = 231 g

T₂ = 86.9°C

T = 72.4°C

Based on Black Principle:

Q absorbed = Q released

m₁c(T - T₁) = m₂c(T₂ - T)

m₁(T - T₁) = m₂(T₂ - T)

m₁(72.4 - 10.2) = 231(86.9 - 72.4)

62.2m₁ = 3349.5

m₁ = 53.85 g