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2) A student performs this reaction in the laboratory, and collects the hydrogen gas over water. The student collects 215.8 mL of gas. The total pressure is 755.2 mmHg and the temperature is 22.0 oC. c) Use the ideal gas law to calculate how many moles of hydrogen were produced in the reaction

1 Answer

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Answer: 0.0086 moles of hydrogen are produced.

Step-by-step explanation:

According to ideal gas equation:


PV=nRT

total pressure = 755.2 mm Hg

pressure of water at
22^0C = 19.8 mm Hg

P = pressure of hydrogen = (755.2-19.8) mm Hg = 735.4 mm Hg = 0.97 atm

(760 mm Hg = 1atm)

V = Volume of gas = 215.8 ml = 0.2158 L

n = number of moles

R = gas constant =
0.0821Latm/Kmol

T =temperature =
22.0^0C=(22.0+273)K=295K


n=(PV)/(RT)


n=(0.97atm* 0.2158L)/(0.0821 L atm/K mol* 295K)=0.0086moles

Thus 0.0086 moles of hydrogen are produced.

User Asif Rehan
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