Mass of KCl= 88.4g
Molar mass of KCl=39+35.5
=74.5
The Moles of KCl= 88.4/74.5
=1.186
If for the 2 moles of KCl there are 3 moles of oxygen
so
1 mole of KCl will give=3/2=1.5 moles of oxygen
1.186 moles of KCl will give =1.51.186=1.779 oxygen
32 the molar mass of oxygen
so its mass will be
1.779 32=56.928
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