Question

A hot metal is placed in 100.0 g sample of water and it causes the temperature of the water to increase from 25 C to 27 C. How many joules of energy did the water absorb from the metal?

Answer 1

Answer: $836.8\ J$

Explanation:

Given

Mass of water in the sample is $m=100\ g$

Temperature changes from $25^{\circ}C$ to $27^{\circ}C$

Change in temperature is $\Delta T=27-25=2^{\circ}C\ \text{or}\ 2\ K$

We know, specific heat of water is $c=4.184\ J/g-K$

Heat absorbed is given by

$\Rightarrow Q=mc\Delta T\\\Rightarrow Q=100\times 4.184\times 2\\\Rightarrow Q=836.8\ J$

Thus, water absorbs $836.8\ J$ of heat from hot plate.