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TyrannosaureBeta9806

Hello!

I do not get Bronsted Lowry theory well. I just get that an acid is H+ donor while a base is a H+ acceptor.

My teacher wrote the following on the board but I do not get, are both equation the same? Why is one an equilibirum while the other isnt. I thought its the same .

A base accepts H+ in water

NH3(base) + H+ -> NH4+

NH3 + H2O <-> NH4+ + OH-

Mélissa S

Hello there, learning supernova! 😁

We're delighted that you're using Alloprof!

You already understand the basic Bronsted–Lowry idea :

• Acid = H⁺ donor
• Base = H⁺ acceptor.

In the first equation,

• NH₃ (ammonia) is acting as a base and accepts H⁺.
• H⁺ is just “given” to NH₃.

It's a complete reaction.

In the second equation, at equilibrium,

• NH₃ is still the base.
• But H⁺ doesn’t exist freely in water. Instead, water donates H⁺ (acting as an acid) and becomes OH⁻.

This reaction doesn’t go 100% to products because NH₃ is a weak base. Most ammonia molecules stay as NH₃ in water. That’s why it’s an equilibrium.

I suggest this worksheet for your revision.

https://www.alloprof.qc.ca/en/students/vl/chemistry/theories-on-acids-and-bases-arrhenius-c1058

Please write to us if you have any further questions. 😊

See you soon on the Help Zone! 😎