Question

Which sequence of coefficients will balance the following equation?

Mg(s) + O2 (g) -> 2MgO (s)
A) 1, 1, 2
B) 4, 1, 2
C) 3, 1, 2
D) 2, 1, 2

Answer 1

D

Step-by-step explanation:

Based on atom count, 2 atoms of magnesium reacts with 1 atom of oxygen to produce 2 moles of magnesium oxide

Answer 2

The correct sequence of coefficients to balance the chemical equation 2H2 + O2 → 2H2O is 2:1:2, which reflects the lowest whole-number ratio that maintains a balance of atoms on both sides of the equation.

Step-by-step explanation:

The sequence of coefficients that will balance the chemical equation 2H₂ + O₂ → 2H₂O is represented by a 2:1:2 ratio. This convention means using the lowest whole-number ratio for the coefficients to maintain a balanced chemical equation. Although the equation is already balanced with a coefficient sequence of 2:1:2, multiple ratios that maintain the proportions, such as 4:2:4 or 22:11:22, will also result in a balanced equation.

The coefficient is essentially a multiplier for the number of atoms of each element represented in the equation, ensuring that the law of conservation of mass is satisfied. Thus, changing the coefficients adjusts the number of atoms on each side of the equation. For example, when you see '4H₂' that means there are 4 molecules of hydrogen, each consisting of 2 hydrogen atoms, so we have a total of 8 hydrogen atoms.