eisenhauerdasia
Answered

The chemical equation below shows the burning of magnesium (Mg) with oxygen (O2) to form magnesium oxide (MgO).


2Mg + O2 mc009-1.jpg 2MgO


The molar mass of O2 is 32.0 g/mol. What mass, in grams, of O2 is required to react completely with 4.00 mol of Mg?

2.00

Verified Answer :

sciencific

for every 2 mole Mg we need 1 mole O2 ( based on the equation). since there is 4 mole Mg we need 2 mole O2. one mole O2 is 32 gram so 2 mole would be 64 grams.

Answer: 64 grams of \(O_2\) will be required to react completely with 4 moles of Mg.

Explanation: The chemical equation of burning of magnesium is given by:

\(2Mg(s)+O_2(g)\rightarrow 2MgO(s)\)

By stoichiometry,

2 moles of Magnesium require 1 mole of oxygen to produce 2 moles of MgO.

\(\text{4 moles of Magnesium will require}=\frac{1}{2}\times 4=2\text{ moles of }O_2\)

Amount of \(O_2\) required to form MgO can be calculated by:

\(\text{Mass of }O_2 \text{ required}=Moles\times \text{Molecular mass of }O_2\)

Molecular mass of \(O_2=32g/mol\)

\(\text{Mass of }O_2\text{ required}=2moles \times 32g/mol\)

                               = 64 grams

Related Questions