I don t understand this question. Help me please. Explain how you do it because i don t know what to do.?

Pre-requisite knowledge :
H = m c ΔT

where,
H : heat absorbed/lost by an object
m : mass of the object in g
c : specified heat capacity of the object in J/(g °C)
(For water, c = 4.184 J/(g °C))
ΔT : temperature increased/decreased when heat is absorbed/lost by the object.


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Calculate the heat lost in a chemical reaction inside a calorimeter when it causes 150 g of water to increase in temperature by 18.0°C

Consider heat absorption by water :
m = 150 g
c = 4.184 J/(g °C))
ΔT = 18.0°C

Heat gained by water
= m c ΔT
= (150 g) × [4.184 J/(g °C)] × (18.0°C)
= 11300 J

Heat lost in the chemical reaction
= Heat gained by water
= 11300 J ...... (Ans)

(4.184 J/g·°C) x (150 g) x (18.0 °C) = 11297 J