Question

How much heat is released as a 5.89 kg block of aluminum cools from 462 °C to 315 °C. The specific heat capacity of aluminum is 0.900 J/(g*K)

Answer 1

779000 J First determine the change in temperature 462=315 = 147 Since degrees C is the same unit size as degrees K, we can consider the change to be in Kelvin units. Now we have three measurements. 5890 grams, 147 K, and 0.900 J/(g*K). We want a result with the units J. So let's start multiplying and dividing as needed to cancel out everything else. J/(g*K) multiplied by K will cancel out the K term. 0.900 J/(g*K) * 147 K = 132.3 J/g Now multiply by 5890 g to cancel the g term. 132.3 J/g * 5890 g = 779247 J Round to 3 significant figures, giving 779000 J

Answer 2

Mass, m = 5890g
Change in temperature, θ = Final_temperature - Initial_temperature
= 315 - 462°C
= -147°C

Specific heat capacity of aluminum, c = 0.900 J/(g*K) 
=mcθ
=5890g x 0.900 J/(g*K) x -147°C
=-779,247j

Answer would be C.