# How much energy is needed to raise the temperature of 2.0 g of water by 5.0°C?

##### 1 Answer
Jun 7, 2017

$41.8 J$

#### Explanation:

The equation for working out the amount of thermal energy required is $q = m c \Delta T$, where $q$ is the amount of energy, $m$ is the mass being heated up in grams, $c$ is the specific heat capacity of what you're heating up in joules per gram per kelvin, and $\Delta T$ is the change in temperature in degrees Celsius or Kelvin (technically it should be in Kelvin but for a change in temperature, Celsius is the same as Kelvin).
In this case, the mass is 2.0g, the specific heat capacity of water is 4.18J/g/K, and the change in temperature is 5.0°C = 5K, therefore the energy needed to raise it is: $5 \times 2 \times 4.18 = 41.8 J$.
This is only theoretical though, in the real world a lot of heat would be lost to the surroundings, so it would require more energy than this.