Question

what is the heat, q, in joules transferred by a chemical reaction to the contents of a calorimeter containing 125 g of dilute aqueous solution (c = 4.184 j/(g·°c)) if the reaction causes the temperature of the solution to rise from 21.5°c to 24.5°c?

Explanation:

Step1: Calculate the temperature change

$\Delta T=T_{final}-T_{initial}=24.5^{\circ}C - 21.5^{\circ}C=3.0^{\circ}C$

Step2: Use the heat - transfer formula

The formula for heat transfer is $q = mc\Delta T$, where $m$ is the mass, $c$ is the specific heat capacity, and $\Delta T$ is the temperature change.
Given $m = 125\ g$, $c=4.184\ \frac{J}{g\cdot^{\circ}C}$, and $\Delta T = 3.0^{\circ}C$
Substitute the values into the formula:
$q=(125\ g)\times(4.184\ \frac{J}{g\cdot^{\circ}C})\times(3.0^{\circ}C)$
First, calculate $125\times4.184 = 523$
Then, $523\times3.0=1569$

Answer:

$1569\ J$