Question

Calculate the energy required to heat 406.0mg of cyclohexane from 33.5°C to 38.9°C . Assume the specific heat capacity of cyclohexane under these conditions is 1.85·J·g−1K−1 . Be sure your answer has the correct number of significant digits.

Answer 1

Answer:

The heat needed to warm 406.0 mg of cyclohexane from 33.5°C to 38.9°C is 209.22 Joules

Explanation:

$Q=mc\Delta T$

Where:

Q = heat absorbed or heat lost

c = specific heat of substance

m = Mass of the substance  

ΔT = change in temperature of the substance

We have mass of cyclohexane = m = 406.0 mg = 0.4060 g

( 1 mg =0.001 g)

Specific heat of cyclohexane  = c = 1.85 J/g°CK

ΔT = 38.9°C - 33.5°C = 5.4°C =5.4+273.15 K = 278.55 K

Heat absorbed by the cyclohexane :

$Q=0.4060 g\times 1.85 J/gK\times 278.55 K=209.22 J$

The heat needed to warm 406.0 mg of cyclohexane from 33.5°C to 38.9°C is 209.22 Joules