Calculate the mass of magnesium oxide that forms when 9g of magnesium is burned.

In accordance with the condition of the problem, we will compose an equation, arrange the coefficients:
2Mg + O2 = 2MgO – magnesium oxide is released;
Let’s make calculations using the formulas:
M (Mg) = 24.3 g / mol;
M (MgO) = 40.3 g / mol.
Determine the amount of moles of magnesium:
Y (Mg) = m / M = 9 / 24.3 = 0.37 mol.
Let’s calculate the number of moles of magnesium oxide:
X mol (MgO) – 0.37 mol (Mg);
-2 mol -2 mol from here, X mol (MgO) = 2 * 0.37 / 2 = 0.37 mol.
Let’s make a calculation using the formula:
M (MgO) = Y * M = 0.37 * 40.3 = 14.93 g.
Answer: Magnesium oxide weighing 14.93 g was obtained.