The nutritional information on a cereal box shows that one serving of dry cereal has 90 calories (actually kilocalories). If one were to burn a serving of cereal, the amount of heat given off would be sufficient to raise the temperature of 1 kg of water in how many degrees Celsius?

90 °C

Explanation:

First, we must know the specific heat capacity of water, which is defined as the energy required to heat 1 gram of water by one degree Celsius. The specific heat capacity of water is 1 cal·g⁻¹°C⁻¹.

The equation we will use is Q = mcΔt, where Q is the heat energy, m is the mass, c is the specific heat capacity, and Δt is the temperature change. We will rearrange the equation to solve for Δt and substitute the values:

Δt = Q / (mc) = (90 kcal) (1000 cal/kcal) / (1 kg) (1000 g/kg) (1 cal·g⁻¹°C⁻¹) = 90 °C