Question

If you have 24 g of Mg burn in 32 g Oz, how many g of MgO are produced?

Answer 1

Answer:

Mass = 40 g

Explanation:

Given data:

Mass of Mg = 24 g

Mass of O₂ = 32 g

Moles of MgO = ?

Chemical equation:

2Mg +  O₂ → 2MgO

Number of moles of Mg:

Number of moles of  Mg= Mass /molar mass

Number of moles of Mg= 24g / 24/mol

Number of moles of  Mg= 1 mol

Number of moles of O₂  :

Number of moles of O₂  = Mass /molar mass

Number of moles of O₂  = 32g / 32 g/mol

Number of moles of O₂  = 1 mol

Now we will compare the moles of water with hydrogen and oxygen .

                 Mg            :            MgO

                  2               :               2

                  1                :               1

                 O₂              :                MgO

                  1                :                    2

The number of moles of MgO produced by Mg are less it will be limiting reactant.

Mass of MgO:

Mass = number of moles × molar mass

Mass = 1 mol × 40 g/mol

Mass = 40 g