5.00 g of nitrogen is completely converted into an oxide of nitrogen - VCE - SSCE Chemistry - Question 10 - 2002 - Paper 1
Question 10
5.00 g of nitrogen is completely converted into an oxide of nitrogen. The mass of the oxide formed is 19.3 g.
The empirical formula of the oxide would be:
A. NO
B. N... show full transcript
Worked Solution & Example Answer:5.00 g of nitrogen is completely converted into an oxide of nitrogen - VCE - SSCE Chemistry - Question 10 - 2002 - Paper 1
Step 1
Determine the mass of oxygen
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Answer
To find the mass of oxygen that combined with nitrogen, use the mass of the oxide formed and subtract the mass of nitrogen:
extMassofOxygen=extMassofOxide−extMassofNitrogen
Substituting the values gives:
extMassofOxygen=19.3extg−5.00extg=14.3extg
Step 2
Calculate moles of nitrogen and oxygen
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Answer
Now, calculate the number of moles of nitrogen and oxygen. The molar mass of nitrogen (N) is approximately 14.01 g/mol and that of oxygen (O) is about 16.00 g/mol:
Moles of Nitrogen:
ext{Moles of N} = rac{5.00 ext{ g}}{14.01 ext{ g/mol}} \\ \approx 0.357 ext{ mol}
Moles of Oxygen:
ext{Moles of O} = rac{14.3 ext{ g}}{16.00 ext{ g/mol}} \\ \approx 0.894 ext{ mol}
Step 3
Find the simplest mole ratio
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Next, to determine the empirical formula, find the simplest mole ratio by dividing each value of moles by the smaller number of moles:
Ration for Nitrogen:
rac{0.357}{0.357} = 1
Ratio for Oxygen:
rac{0.894}{0.357} \\ \approx 2.5
To express this as a whole number, multiply both ratios by 2:
N:1×2=2O:2.5×2=5
Step 4
Determine the empirical formula
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