For the following question(s), consider the following equation.

2Mg + 02 → 2Mgo
How many grams of MgO are produced when 40.0 grams of 02 react completely with Mg?

60.5 g
202 g
50.4 g
40.3 g
101 g

1 answer

To determine the number of grams of MgO produced, we need to find the molar mass of MgO.

The molar mass of Mg is approximately 24.31 g/mol.
The molar mass of O is approximately 16.00 g/mol.

In the balanced equation, we see that 2 moles of Mg reacts to form 2 moles of MgO.
So, 1 mole of Mg reacts to form 1 mole of MgO.

Therefore, the molar mass of MgO is approximately:
(24.31 g/mol) + (16.00 g/mol) = 40.31 g/mol

Now, we can calculate the number of moles of O2 present in 40.0 grams using its molar mass:
40.0 g / (32.00 g/mol) = 1.25 mol

Since 1 mole of Mg reacts with 1 mole of MgO, the number of moles of MgO produced is also 1.25 mol.

Finally, we can calculate the mass of MgO produced using its molar mass:
1.25 mol * (40.31 g/mol) = 50.39 g

Therefore, the correct answer is 50.4 g.