Question

A copper block is removed from a 310C oven and dropped into 1.10kg of water at 23.0C. The water quickly reaches 33.0C and then remains at that temperature.

What is the mass of the copper block? The specific heats of copper and water are 385 J/(kg?K) and 4190 J/(kg?K) respectively. Express your answer to three significant figures and include the appropriate units.

Answer 1

Answer:

0.432kg or 432g

Explanation:

Copper block is removed from 310C oven.

Mass of water = 1.10kg

Initial temperature of water (θ1) = 23.0C

Final temperature of water (θ2 ) = 33.0C

Specific heat of copper= 385

Specific heat of water = 4190

Let M (copper) be the mass of copper

The amount of heat lost will be absorbed by water

Q (net) = Q(water) + Q(copper) = 0 …………………(1)

Q = MCθ

For water,

Q(water) = M(water) * C(water) * (θ2-θ1)...........(2)

= 1.1 * 4190 * (33.0 -23.0)

= 1.1 *4190 * 10

= 46090J

For copper,

Q(copper) = M(copper) * C(copper) * (33.0 - 310)...........(3)

from equation 1,

Q(copper) = -Q(water)

M(copper) * C(copper) * (33.0 - 310) = - 46090

M(copper) * 385 * (-277) = -46090

M(copper) * 106645 = -46090

M(copper) = -46090 / -106645

M(copper) = 0.432kg

M(copper) = 432g

The mass of copper =432g