179.1 g of water is in a Styrofoam calorimeter of negligible heat capacity. The initial T of the water is 16.1oC. After 306.9 g of an unknown compound at 94.3oC is added, the equilibrium T is 27.4oC.

What is the specific heat of the unknown compound in J/(goC)?

the specific heat of the unknown compound is

Explanation:

Generally the change in temperature of water is evaluated as

Substituting 16.1°C for and 27.4°C for

Generally the change in temperature of  unknown compound is evaluated as

Substituting 27.4°C for and 94.3°C for

Since there is an increase in temperature then heat is gained by water and this can be evaluated as

Substituting 179.1 g  for m , 4.18 J/g.C for (specific heat of water)

Since there is a decrease in temperature then heat is lost by unknown compound and this can be evaluated as

By conservation of energy law

       Heat lost  = Heat gained  

Substituting 306.9 g  for , 8459.6J for

  Therefore    

c is the answer because when something is left after something evaporates that shows the chemical change.

answer; talc and gypsum;