# How much heat is required to raise the temp of 654 g of water from 34.5°C to 89.7°C?

Apr 24, 2016

$151 k J$

#### Explanation:

Amount of energy needed to raise a certain amount of a substance is given by

$E = m \cdot c \cdot \theta$

where $E$ is energy, $m$ is mass, $c$ is the specific heat capacity and $\theta$ is the change in temperature.

The specific heat capacity of water is $4181 \frac{J}{k {g}^{o} C}$.

Mass is given as $654 g$, which in the more useful unit of kilograms is $0.654 k g$.

Change in temperature is also given in the question indirectly, and can be calculated as the difference in the two values, or $89.7 - 34.5 = {55.2}^{o} C$.

Plugging these values into the equation,

$E = 0.654 k g \cdot 4181 \frac{J}{k {g}^{o} C} \cdot {55.2}^{o} C = 150937 J$

$\approx 151 k J$