mass percentage of CuO

mass percentage of CuO

 

 

A mixture of Al2O3(s) and CuO(s) weighing 18.371 mg was heated under H2 in a thermogravimetric analysis experiment. Under these conditions CuO is reduced to Cu but Al2O3 does not react.

When all the CuO had been reduced the final mass was 17.462 mg.

Calculate the mass percentage of CuO in the original mixture.

 

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간단히 나타내기 위해, mg을 g으로 사용.

 

처음 질량(Al2O3+CuO) – 나중 질량(Al2O3+Cu) = 산소 원자(O)의 질량

18.371 g - 17.462 g = 0.909 g O

 

CuO의 몰질량 = Cu + O = 63.55 + 16.00 = 79.55 g/mol 이므로,

혼합물 중 CuO의 질량을 계산하면,

0.909 g O × (79.55 g CuO / 16.00 g O) = 4.5194 g CuO

 

혼합물 중 CuO의 함량을 계산하면,

(4.5194 g / 18.371 g) × 100 = 24.6%

 

 

답: 24.6%