Question

135 Joules of heat are required to increase the temperature of 10.0 grams of an unknown metal from 25.0∘C to 40.0∘C:

Answer 1

Answer:

270 Joules

Explanation:

The specific heat capacity equation will be used for this question i.e.

Q = m. c. ΔT

Where; Q = Amount of heat

m = mass of substance

C = specific heat capacity of

substance

ΔT = change in temperature

(Final temp - initial temp)

However, for this unknown metal, we need to find the specific heat first by saying; C = Q / mΔT

Q= 135J, C=?, m= 10g, ΔT = (40-25 = 15°C)

C = 135 / 15 × 10

C = 135/150

C = 0.9 J/g°C

If the specific heat capacity of the unknown metal is 0.9 J/g°C, then at a mass of 20.0g, and a ΔT of 15°C, the amount of heat needed is:

Q = m. c. ΔT

Q = 20 × 0.9 × (40-25)

Q = 18 × 15

Q = 270J

270 Joules of heat is needed to increase the temperature of 20g of the metal from 25 - 40°C