metal Ca water H2 gas 30℃ 988 mmHg 641 mL H2 mass

metal Ca water H2 gas 30℃ 988 mmHg 641 mL H2 mass

 

 

Hydrogen gas generated when calcium metal reacts with water is collected.

The volume of gas collected at 30°C and pressure of 988 mmHg is 641 mL.

What is the mass (in grams) of the hydrogen gas obtained?

The pressure of water vapor at 30°C is 31.82 mmHg.

 

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수소 기체의 압력 = 988 mmHg – 31.82 mmHg

( 참고 https://ywpop.tistory.com/3490 )

 

= 956.18 mmHg

= 956.18/760 atm

 

 

 

PV = nRT

( 참고 https://ywpop.tistory.com/3097 )

 

n = PV / RT

= [(956.18/760) (0.641)] / [(0.08206) (273.15+30)]

= 0.03242 mol H2

 

 

 

0.03242 mol × (2 g/mol) = 0.06484 g H2

 

 

 

답: 0.06484 g