Question

A 15.6 g sample of ethyl alcohol absorbs 0.207 kcal of energy as it is heated. If the initial temperature of the ethanol was 21.5 °C, what is the final temperature of the ethanol? (cethanol = 0.58 kcal/kg °C)

22.9 ° C
25.0 ° C
44.4 ° C

Answer 1

m = mass of sample = 15.6 g = 0.0156 kg

c = specific heat of the sample = 0.58 kcal/kgC = 580 cal/(kgC)

`T_(i)` = initial temperature = 21.5 C

`T_(f)` = final temperature = ?

Q = heat absorbed = 0.207 kcal = 207 cal

using the equation

Q = m c (
`T_(f)`-
`T_(i)`)

207 = (0.0156) (580) (
`T_(f)`-21.5)

`T_(f)` = 44.4