Question

A 235-g sample of a substance is heated to 320 ∘C and then plunged into a 105-g aluminum calorimeter cup containing 175 g of water and a 17-g glass thermometer at 10.5 ∘C. The final temperature is 35.0∘C. The value of specific heat for aluminium is 900 J/kg⋅C∘ , for glass is 840 J/kg⋅C∘ , and for water is 4186 J/kg⋅C∘ . Part A What is the specific heat of the substance? (Assume no water boils away.) Express your answer using three significant figures.

Answer 1

Part A :

given

A 235-g sample of a substance

is heated to 320 ∘C and

then plunged into a 105-g aluminum

calorimeter cup containing 175 g of water

and a 17-g glass thermometer at 10.5 ∘C.

The final temperature is 35.0∘C.

The value of specific heat for aluminium is 900 J/kg⋅C∘ ,

for glass is 840 J/kg⋅C∘ ,

and for water is 4186 J/kg⋅C∘

0.235 X S X ( 320 - 35 ) = 0.105 X 900 X ( 35 - 10.5 ) + 0.105 X 4186 X ( 35 - 10.5 ) + 0.017 X 840 X ( 35 - 10.5 )

S X 66.97 = 2315.25 + 10768.48 + 349.86

S = 13433.59 / 66.97

S = 200.5911 J / kg^oC