수상포집. 1.24 g Mg room temperature 780 mmHg

수상포집. 1.24 g Mg room temperature 780 mmHg

 

 

Magnesium reacts with excess hydrochloric acid to produce hydrogen gas and magnesium chloride. The hydrogen gas is collected over water.

If the student used 1.24 g of magnesium metal, what volume of hydrogen gas would be collected at room temperature?

The combined pressure at the point is found to be 780 mmHg.

 

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균형 맞춘 화학 반응식

Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)

 

 

 

Mg의 몰질량 = 24.31 g/mol 이므로,

1.24 g / (24.31 g/mol) = 0.0510 mol Mg

 

 

 

Mg : H2 = 1 : 1 계수비(= 몰수비) 이므로,

생성되는 H2의 몰수 = 0.0510 mol

 

 

 

room temperature = 20℃

 

 

 

20℃에서 물의 수증기압 = 17.535 mmHg

( 참고 https://ywpop.tistory.com/5014 )

 

 

 

수소 기체의 분압 = 780 mmHg - 17.535 mmHg = 762.465 mmHg

( 참고 https://ywpop.tistory.com/3490 )

 

 

 

PV = nRT

( 참고 https://ywpop.tistory.com/3097 )

 

V = nRT / P

= (0.0510) (0.08206) (273.15+20) / (762.465/760)

= 1.223 L

 

 

 

답: 1.22 L