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Substance Specific Heat (cal/g°C) Specific Heat (J/g°C) water 1.00 4.18 steam 0.96 4.02 alcohol 0.59 2.47 ice 0.50 2.09 wood 0.41 1.72 oil (vegetable) 0.40 1.67 air 0.28 1.17 aluminum 0.22 0.92 brick 0.22 0.92 glass 0.22 0.92 sand 0.20 0.84 copper 0.09 0.38 mercury 0.03 0.13 A 16.6 g sample of alcohol absorbs 890 Joules of energy as it is heated. If the initial temperature of the alcohol was 21.5 °C, what is the final temperature of the ethanol?(A) 41.0 ºC(B) 19.5 ºC(C) 43.2 ºC

User JSR
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2 Answers

4 votes

Answer:

The answer is the letter C) 43,2°C

Step-by-step explanation:

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User Foster Bass
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7 votes

Answer:

C) 43,2°C

Step-by-step explanation:

Sensible heat is the amount of thermal energy that is required to change the temperature of an object, the equation for calculating the heat change is given by:

Q=msΔT

where:

  • Q, heat that has been absorbed or realeased by the substance [J]
  • m, mass of the substance [g]
  • s, specific heat capacity [J/g°C]
  • ΔT, changes in the substance temperature [°C]

To solve the problem, we clear ΔT of the equation and then replace our data:

Q=890 [J],

m=16,6 [g],

s=2,74 [J/g°C]

Q=msΔT.......................ΔT=Q/ms

Δ
T=(890 J)/(16,6g*2,47(J)/(gC))=21,7°C

As:

ΔT=Tfinal-Tinitial

Tfinal=ΔT+Tinitial

Tfinal=21,7+21,5=43,2°C

The final temperature of the ethanol is 43,2°C.

User Alberto Santini
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