The balanced equation for the reaction of ammonia (NH₃) and carbon dioxide (CO₂) to form urea (CH₄N₂O) and water (H₂O) is:

2 NH₃ + CO₂ → CH₄N₂O + H₂O

Here's a breakdown:

* Reactants:

* 2 NH₃ (two molecules of ammonia)

* CO₂ (one molecule of carbon dioxide)

* Products:

* CH₄N₂O (one molecule of urea)

* H₂O (one molecule of water)

This equation is balanced because:

* Atoms of each element are equal on both sides:

* Nitrogen (N): 2 on each side

* Hydrogen (H): 8 on each side

* Carbon (C): 1 on each side

* Oxygen (O): 2 on each side

This reaction is a key process in the production of urea, an important fertilizer.