Question

the mass of one litre of oxygen is 1.4 gram. volume of oxygen needed to react with 21 gram of magnesium whose equivalent is 0.5 mole is.........
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Answer 1

Answer:

The moles of Mg consumed are:

21g ÷ 24.3 g/mol = 0.86 moles of Mg

To relate moles Mg and O2, a balanced reaction is needed: Mg + 1/2 O2 --> MgO

The amount of O2 consumed is:

(0.86 mole Mg) * (1/2 mole O2 ÷ 1 mole Mg) = 0.43 mole O2

The mass of O2 consumed is:

0.43 mole O2 * 32 g/mole O2 = 14 grams

The volume of O2 consumed is:

14 g ÷ 1.4 g/L = 10 L

Explanation: