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4g of calcium metal is burned in oxygen of air to form calcium oxide. (Ca = 40, O= 16, at STP: 32g of oxygen has 22.4L)

Find the mass of the calcium oxide

Find the volume of the required air if the volume of oxygen is 1/5 time of the volume of air.?
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waveslife

Answer:

m=4 g Ca

M=ArCa+ArO=56 g/mol

Ca+O2-2CaO

nCa= m/M= 4/40=0.1 moles of Ca

the ratio of moles: 1 mole Ca:2 moles CaO

0.1 moles Ca =0.2 moles CaO

n=m/M

m=n×M

m=0.2×56=11.2 g CaO