How many joules of heat are absorbed when 1000g of water is heated from 18Celsius to 85celsius?

Answer + Explanations

Calculate heat absorption using the formula:

Q = mc∆T

Q means the heat absorbed, m is the mass of the substance absorbing heat, c is the specific heat capacity and ∆T is the change in temperature.

The heat absorbed is calculated by using the specific heat of water and the equation ΔH=cp×m×ΔT. 4. Water is vaporized to steam at 100oC. The heat absorbed is calculated by multiplying the moles of water by the molar heat of vaporization.

You can do this easily: just multiply the heat capacity of the substance you're heating by the mass of the substance and the change in temperature to find the heat absorbed.

To calculate the amount of heat released in a chemical reaction, use the equation Q = mc ΔT, where Q is the heat energy transferred (in joules), m is the mass of the liquid being heated (in kilograms), c is the specific heat capacity of the liquid (joule per kilogram degrees Celsius), and ΔT is the change in ...

Q = mc∆T. Q = heat energy (Joules, J) m = mass of a substance (kg) c = specific heat (units J/kg∙K) ∆ is a symbol meaning "the change in"

Precisely, water has to absorb 4,184 Joules of heat (1 calorie) for the temperature of one kilogram of water to increase 1°C. For comparison sake, it only takes 385 Joules of heat to raise 1 kilogram of copper 1°C.

A reaction that absorbs heat is endothermic. Its enthalpy will be positive, and it will cool down its surroundings. This reaction is exothermic (negative enthalpy, release of heat).

Quantitative experiments show that 4.18 Joules of heat energy are required to raise the temperature of 1g of water by 1°C. Thus, a liter (1000g) of water that increased from 24 to 25°C has absorbed 4.18 J/g°C x 1000g x 1°C or 4180 Joules of energy.