Question

A beaker contains 450g of water at a temperature of 24C, The therman capacity of the beaker is negligible and no heat is gained by, or lost to, the atmosphere. Calculate the mass of ice, initially at 0C, that must be mixed with the water so that the final temp of the contents of the beakers is at 8C.

Answer 1

Given:

450 grams of water (Tw = 24 C) 
Thermal capacity of the beaker = negligible
Q = 0 
Tice = 0 C
Tfinal = 8 C

450g * (Tf - Tw) + m_ice * (Tice - Tw) = 0

450g * (8 - 24) + m_ice (0 - 24) = 0 

solve for m_ice