How to find the volume of oxygen gas collected in water decomposed?
April 14, 2009 in Chemistry
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Smilely asked:
When water is subjected to an electric current, it decomposes to hydrogen and oxygen gas. If 1.00g of water is decomposed at 1.00 atm and 25 degree Celsius, what volume of oxygen gas is collected?
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Let’s first balance the equation…
2H2O -> 2H2 + O2
Then let’s convert 1g of H2O to moles of H2O…
1.00g H2O x (1 mole )
……….1……..(18.01g )
= .05552471 moles H2O
Then let’s use the ideal gas equation to find the answer
PV = nRT
P = 1.00 atm
V = ?
n = .05552471 moles H2O
R = .0821
T = 25 degrees Celsius (or 298 K)
V = nRT
……..P
V = (.05552471)(.0821)(298)
……………..1.00 atm
Volume (V) = 1.35845641 Liters
Rounded to 3 sig figs: 1.36 Liters