An unknown material, m1 = 0.49 kg, at a temperature of t1 = 92 degrees c is added to a dewer (an insulated container) which contains m2 = 1.1 kg of water at t2 = 21 degrees c. water has a specific heat of cw = 4186 j/(kg⋅k). after the system comes to equilibrium the final temperature is t = 31 degrees c. detemine the specific heat of unknown material.

Explanation:

We know that heat relates to mass, specific heat and variation of temperature experimented because of this heat through the equation . The heat released by the unknown material is absorbed by water, so we have , and we can write:

Since thermal equilibrium is reached we know that , where we have added to convert the temperature from Celsius to Kelvin, as we must do. Since we want the specific heat of the unknown material, we do:

Which for our values is:

- measure reactants precisely. ( first choice)

- stir to the reaction take place. ( second choice)

- wait patiently until the reaction completes. ( fourth choice)

- make sure to recover as much copper as possible. ( last choice)

ammonium chloride & tallow