Homework Help: chemistry

Posted by Bryan on Monday, May 7, 2012 at 8:55pm.

2H2+1O2=2H2O delta H=-136 kJ
A) how many joules are released when 35.0 grams H2O form
B)how many grams of hydrogen burn when 278 kJ are released.
C) Draw a potential energy diagram of this reaction.

chemistry - DrBob222, Monday, May 7, 2012 at 9:30pm
a)
136 kJ released when 36 g H2O formed; therefore, 136 x 35/36 = ?kJ released for 35 g. Convert to J.

b)
136 kJ released when 4 g H burns. So
4 g H2 x 278/136 = ? g H burn when 278 kJ released.

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