Let’s solve this step by step.
We are balancing a chemical equation. From the image, we can see that the reaction involves magnesium (Mg) and oxygen (O), and it forms magnesium oxide (MgO). The unbalanced equation is:
Mg + O₂ → MgO
(Note: Oxygen is diatomic — it exists as O₂ in nature — so we must write it that way.)
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Step 1: Count atoms on each side
Left side (reactants):
- Mg = 1
- O = 2 (because O₂ has two oxygen atoms)
Right side (products):
- Mg = 1
- O = 1
→ Oxygen is not balanced! Left has 2, right has 1.
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Step 2: Pick an element that is not equal on both sides
Oxygen is unequal. Let’s fix that first.
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Step 3: Add a coefficient to balance oxygen
On the right, we have only 1 oxygen atom in MgO. To get 2 oxygen atoms on the right (to match left), put a
2 in front of MgO:
Now:
Mg + O₂ → 2MgO
Check atoms again:
Left:
- Mg = 1
- O = 2
Right:
- Mg = 2 (because 2 × MgO means 2 Mg atoms)
- O = 2 (2 × O = 2 oxygen atoms)
→ Now oxygen is balanced, but magnesium is NOT! Left has 1 Mg, right has 2 Mg.
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Step 4: Adjust coefficients to balance magnesium
Put a
2 in front of Mg on the left:
2Mg + O₂ → 2MgO
Now check:
Left:
- Mg = 2
- O = 2
Right:
- Mg = 2
- O = 2
✔ Everything is balanced!
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Final Answer:
2Mg + O₂ → 2MgO
Parent Tip: Review the logic above to help your child master the concept of balancing act worksheet answer key.
