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77julia77 [94]
3 years ago
14

The same heat transfer into identical masses of different substances produces different temperature changes. Calculate the final

temperature when 1.00 kcal of heat transfers into 1.00 kg of the following, originally at 20.0ºC : (a) water; (b) concrete; (c) steel; and (d) mercury.
Chemistry
1 answer:
myrzilka [38]3 years ago
7 0

Answer: final temperatures will be

a) water 21 C

b) concrete  20.005 C

c) steel   20.008 C

d) mercury  53 C

Explanation:

Change in temp dT = dH / (mass x specific heat)

Specific heat of these materials can be found from many sources:

water = 1 kcal / kg C

concrete = 210 kcal / kg C

steel = 114 kcal / kg C

mercury = 0.03 kcal /kg C

So dT (water) from 1 kcal heat into 1 kg water = 1 kcal / (1 kg x 1 kcal/kg C) = 1 C therefore the final temperature is 20 + 1 = 21 C

But dT (steel) = 1 kcal / (1kg x 114 kcal/kg C) = 0.008 C so the final temperature is 20 + 0.008 = 20.008 C

The results for concrete and mercury are calculated in the same way

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3 years ago
Determine the free energy(ΔG) from the standard cell potential (Ecell0 ) for the reaction:2ClO2-(aq)+Cl2(g)→2ClO2(g)+ 2Cl-(aq)wh
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<u>Answer:</u> The \Delta G^o for the given reaction is -7.84\times 10^4J

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