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Some thermodynamic properties of ethanol are listed in the table.
Thermodynamic PropertiesProperty
Value c (solid) 0.5 J/g °C c (liquid)
1.0 J/g °C c (gas) 2.0 J/g °C
Melting Point −114 °C
Boiling Point 78 °C
How much heat is released when 60.0 g of ethanol cools from 70 °C to 43 °C?
A. 1,600 J
B. 1500 J
C. 810 J
D. 750 J

User Mrdeadsven
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2 Answers

3 votes
A I almost sure of that
User VladZams
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4 votes

Answer:

A) 1,600 J

Step-by-step explanation:

Given:

Mass of ethanol, m = 60.0 g

Initial temperature, T1 = 70 C

Final temp, T2 = 43 C

To determine:

Heat (q) lost as ethanol is cooled

Formula:

The heat lost by a substance is given as:


q = -mc\Delta T = -mc(T2-T1)

In the case of ethanol at 70 C, it exists as a liquid therefore, the specific heat capacity c = 1.0 J/gC


q = -60.0 g*1.0 J/gC*(43-70)C= 1620 J

User Erik Noren
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