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chemistry

A 5.00 g sample of impure lead(II) nitrate was heated. The volume of oxygen formed was
0.16dm3 measured at r.t.p. The impurities did not decompose.
Calculate the percentage of lead(II) nitrate in the sample.

2Pb(NO3)2 → 2PbO + 4NO2 + O2

Number of moles of O2 formed = ................................ .......

Number of moles of Pb(NO3)2 in the sample = ................................ .......

Mass of one mole of Pb(NO3)2 = 331 g

Mass of lead(II) nitrate in the sample = ................................ ....... g

Percentage of lead(II) nitrate in sample = ................................ .....

Reply 1

username3249896

Number of moles of O2 formed = ................................ ....... 6.67 x 10^-3 mol

Number of moles of Pb(NO3)2 in the sample = ................................ ....... 0.0133 mol

Mass of one mole of Pb(NO3)2 = 331 g

Mass of lead(II) nitrate in the sample = ................................ ....... g 4.41 g

Percentage of lead(II) nitrate in sample = ................................ .....88.3%