What is the amount of heat required to increase the relative temperature of an object by 0.8cal / gm ° c to 20 c of a mass of 50 g? 
Answers
Answer:
0.43jg
Explanation:
Mass of the metal, m = 0.20 kg = 200 g
Initial temperature of the metal, T1 = 150 oC
Final temperature of the metal, T2 = 40 oC
Calorimeter has water equivalent of mass, m = 0.025 kg = 25 g
Volume of water, V = 150 cm3
Mass (M) of water at temperature T = 27oC:
150×1=150g
Fall in the temperature of the metal:
ΔTm=T1-T2 =150−40=110oC
Specific heat of water, Cw=4.186J/g/K
Specific heat of the metal =C
Heat lost by the metal, =mCT .... (i)
Rise in the temperature of the water and calorimeter system: T1−T=40−27=13oC
Heat gained by the water and calorimeter system: =m1CwT=(M+m)CwT ....(ii)
Heat lost by the metal = Heat gained by the water and colorimeter system
mCΔTm=(M+m)CwTw
200×C×110=(150+25)×4.186×13
C=(175×4.186×13)/(110×200)=0.43Jg