If 51.6 mL of ethanol (density = 0.789 g/mL) initially at 6.4°C is mixed with 48.9 mL of water (density = 1.0 g/mL) initially at 29.1°C in an insulated beaker, and assuming that no heat is lost, what is the final temperature of the mixture?

Answer 1

use density to convert volume ethanol and volume H2O to mass in grams. Then
[mass ethanol x specific heat ethanol x (Tfinal-Tinitial)] + [mass H2O x specific heat H2O x (Tfinal-Tinitial)] = 0.
Substitute and solve for Tfinal. You must look up specific heat ethanol and H2O.