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1.0 g of magnesium is burnt with  0.56 g O2 in a closed vessel. Which reactant is left in excess and how much?
(At. wt. Mg = 24; O = 16)

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Important Questions on Some Basic Concepts of Chemistry

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The ratio of masses of oxygen and nitrogen in a particular gaseous mixture is 1:4. The ratio of their number of molecules is
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If the Avogadro number NA, is changed from 6.022 × 1023 mol-1 to 6.022 × 1020 mol1 this would change
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