2H2O2(l) ΔH = -196 kJ H2O2(l) 5.00 g

2H2O2(l) ΔH = -196 kJ H2O2(l) 5.00 g

 

 

Hydrogen peroxide can decompose to water and oxygen by the reaction:

2H2O2(l) → 2H2O(l) + O2(g) ... ΔH = –196 kJ

Calculate the quantity of heat released

when 5.00 g of H2O2(l) decomposes at constant pressure.

 

 

 

2H2O2(l) → 2H2O(l) + O2(g) ... ΔH = –196 kJ

 

2몰 H2O2의 분해열이 –196 kJ 이므로,

ΔH = –196 kJ / 2 mol

= –98 kJ/mol

---> H2O2 1몰당 분해열

 

 

 

H2O2의 몰질량 = 34.01 g/mol 이므로,

5.00 g / (34.01 g/mol) = 0.147 mol H2O2

( 참고 https://ywpop.tistory.com/7738 )

 

 

 

ΔH = 0.147 mol × (–98 kJ/mol)

= –14.406 kJ

 

 

 

답: ΔH = –14.4 kJ

 

 

 

 

[키워드] H2O2의 분해열 기준