Question

Calculate the enthalpy change to raise the temperature of 180.0 g of water from 10.0°C to 40.0°C. The molar heat capacity for water is 75.3 J/Kmol. a. What values have you been given? b. What value are you trying to find? c. Which heat equation do you need? d. Now solve the problem.

Answer 1

Answer:

22572J

Explanation:

a) The following values have been given:

Mass of water = 180.0g

Initial temperature = 10°C

Final temperature = 40°C

molar heat capacity for water = 75.3J/Kmol

To calculate the specific heat capacity of water (c), we divide the molar heat capacity by molar mass of water (18g/mol)

That is; 75.3/18

= 4.183 Jg/K

b) The enthalpy change denoted by ∆H is the value we are trying to find.

c) To find enthalpy change (∆H), we use the formula:

∆H = m × c × ∆T

Where; m= mass

c= specific heat capacity

∆T= change in temperature =

(final temp - initial temp)

∆H = m × c × ∆T

∆H = 180 × 4.18 × (40-10)

∆H = 180 × 4.18 × 30

∆H = 22572J