How Much Heat Does One Kilogram of Water Absorb When Heated from 5°C to 95°C?
Understanding Heat Absorption in Water: When you heat water, it absorbs heat energy, which raises its temperature. This absorption of heat follows a clear formula that you can use to calculate the exact amount of energy required. In this article, we will discuss the process and calculation of heat absorption for one kilogram of water heated from 5°C to 95°C.
Understanding the Formula
The formula for calculating the heat absorbed by a substance is:
Q m cΔT where Q is the heat absorbed (in Joules, J) m is the mass of the substance (in kilograms, kg) c is the specific heat capacity of the substance (in Joules per kilogram per degree Celsius, J/kg°C) ΔT is the change in temperature (in degrees Celsius, °C)Applying the Formula to Water
Let's use the formula to find out how much heat one kilogram of water absorbs when heated from 5°C to 95°C:
Mass (m) 1 kg Specific heat capacity (c) of water 4200 J/kg°C Initial temperature (Ti) 5°C Final temperature (Tf) 95°CThe change in temperature (ΔT) is calculated as:
ΔT Tf - Ti
ΔT 95°C - 5°C
ΔT 90°C
Calculation of Heat Absorbed (Q)
Now, substitute the values into the formula Q m c ΔT:
Q 1 kg × 4200 J/kg°C × 90°C
Q 378000 J
or
Q 378 kJ
Summary and Implications
The calculation shows that one kilogram of water absorbs 378,000 Joules (or 378 kilojoules) of heat when it is heated from 5°C to 95°C. This principle is fundamental in thermodynamics and is widely applied in heat-related calculations, such as in heating, cooling systems, and other thermal processes.
Additional Considerations
It's important to note that the specific heat capacity of water varies slightly with temperature, but for practical purposes, it is often assumed to be constant over small temperature ranges. For more precise calculations, the specific heat capacity at a specific temperature would be needed.
Understanding the heat absorption of water is crucial for various fields, including chemical engineering, mechanical engineering, and environmental science, where heat transfer and energy management are critical.