Question

A 85.2 g copper bar was heated to 221.32 degrees Celsius and placed in a coffee cup calorimeter containing 4250 mL of water at 22.55 degrees Celsius. The final temperature of the water was recorded to be 26.15 degrees Celsius. How much heat was gained by the water?

Answer 1

Answer:- 64015 J

Solution: There is 4250 mL of water in the calorimeter at 22.55 degree C.

density of water is 1 g per mL.

So, the mass of water = $4250mL(\frac{1g}{1mL})$  = 4250 g

Final temperature of water after adding the hot copper bar to it is 26.15 degree C.

So, $\Delta T$ for water = 26.15 - 22.55 = 3.60 degree C

Specific heat for water is 4.184 $\frac{J}{g.^0C}$

The heat gained by water is calculated by using the formula:

$q=mc\Delta T$

where, q is the heat energy, m is mass and c is specific heat.

Let's plug in the values in the formula and do the calculations:

$q=4250g*\frac{4.184J}{g.^0C}*3.60^0C$

q = 64015 J

So, 64015 J of heat is gained by the water.