How to find the mass and volume when given this information?

Question

m= mass

c = specific heat

delta T= temperature change

In today’s experiment, you will calculate how much cold liquid (milk) must be added to a hot liquid (coffee) so that the final temperature of the mixture is 90 deg C. The coffee will be at 95 deg C and the milk will be at 4 deg C.

Specific heat is 4.184 J / mL for milk and coffee and density is 1.0 g / mL for milk and coffee .

m(coffee) x C(coffee) x ΔT(coffee) = - m(milk) x C(milk) x ΔT(milk)

my equation : m(coffee) x C(4.184 J/g deg C) x ΔT(5 'C)= m(milk) x C(4.184 J/g deg C) x ΔT(86 'C)

problem:

Solve for mass of milk m(milk) and then use the density of milk to convert the mass of milk to volume of milk needed.

Answer 1

The heat gained by the cold milk must equal the heat lost by the hot coffee (conservation of matter)

Heat gained by cold milk = q = mC∆T = (m)(4.184 J/mlº)(90º - 4º) = 359.8 m

Heat lost by hot coffee = q = mC∆T = (m)(4.184 J/mlº)(95º -90º) = 20.92 m

YOU CANNOT ANSWER THIS QUESTION UNLESS YOU KNOW THE MASS OR VOLUME OF COFFEE.

You have two unknowns and only one equation, i.e. -q_coffee = q_milk