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Chemistry
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1. The specific heat of mercury metal is 0.138J/gK. How much heat, in joules, is required to heat a 127 gram sample of mercury from -18.5oC to 107.2oC? Enter your answer in scientific notation with no units. 

2. What is the specific heat of a substance (in J/g.K) if a 52.2 gram sample of the substance increases in temperature by 17.8 when it is heated by 230.0 joules? 

3.  3C(s) + 4H2(g) + 5O2(g) ---> 3CO2(g) + 4H2O(l) ΔH= -2323.7 kJ/mol

How much heat would be released when 34.1 g of O2 react? 
Apr 19th, 2015

1.   Heat  =  m x sp. heat x delta T =. (127 g) ( 0.132 j/g K) ( 125.7K)

                =. 2107.2 J

2.  Sp. heat = Q/m x delta T =. 230 J/ (52.2 g) ( 17.8 K )

                                             = 0.248 J / g K

3.  34.1 g = 1.06 mole which is approx.. 1 mole

   So heat released = -2323 KJ/mole  divided by 5

               = -464.6 kJ/mol


Apr 19th, 2015

I have answered your question.

Niru

Apr 19th, 2015

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Apr 19th, 2015
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Apr 19th, 2015
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