Solve the following equations without transposing.

• Fe₃O₄ + 2H₂SO₄ → Fe₂(SO₄)₃ + 2H₂O
• 2Na + Cl₂ → 2NaCl
• CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂
• 2H₂ + O₂ → 2H₂O

To solve the given equations, we will balance each reaction step by step without transposing any elements. Here’s how each reaction can be balanced:

1. Iron(II,III) Oxide and Sulfuric Acid

The reaction is:

Fe₃O₄ + 2H₂SO₄ → Fe₂(SO₄)₃ + 2H₂O

In this equation, we have:

• 3 iron (Fe) atoms on the left, balanced with 2 in the product and 1 in the sulfate.
• 4 oxygen (O) from Fe₃O₄ and 4 from 2H₂SO₄, which balances with the 12 in Fe₂(SO₄)₃ and 2H₂O.

2. Sodium and Chlorine Reaction

The reaction is:

2Na + Cl₂ → 2NaCl

This equation is already balanced:

• 2 sodium (Na) atoms react with 1 molecule of chlorine (Cl₂) to produce 2 sodium chloride (NaCl) units.

3. Calcium Carbonate and Hydrochloric Acid

The reaction is:

CaCO₃ + 2HCl → CaCl₂ + H₂O + CO₂

In this case:

• 1 calcium (Ca), 1 carbon (C), and 3 oxygen (O) are balanced with the products.
• 2 hydrogen (H) from HCl balances with 2 in H₂O.

4. Hydrogen and Oxygen Formation of Water

The reaction is:

2H₂ + O₂ → 2H₂O

This equation is also balanced:

• 4 hydrogen (H) atoms from 2H₂ react with 2 oxygen (O) atoms to produce 2 water (H₂O) molecules.

Each equation is balanced, ensuring that the number of atoms for each element is the same on both sides of the reaction. This method helps in understanding how chemical reactions maintain the law of conservation of mass.