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3 years ago

7

How much heat will be released when 10.0 g of hydrogen peroxide decomposes according to the following reaction: 2H2O2(l) 2H2O(l)

+ O2(g) ΔH = -190 kJ
A. 26 kJ
B. 22 kJ
C. 28 kJ
D. 24 kJ

1 answer:

kramer3 years ago

5 0

C. 28 KJ

AMU of H2O2 = 2(1) + 2(16) = 34 g/mol
10 g / 34 g/mol = 0.294 mol H2O2

0.294 mol / H = 2 mol / 190 KJ
H = 28.9 KJ

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