Ammonia has a Kb of 1.8 × 10−5. Find [H3O+], [OH−], pH, and pOH for a 0.310 M ammonia solution.

[H₃O⁺] = 4.3 × 10⁻¹² mol·L⁻¹; [OH⁻] = 2.4 × 10⁻³ mol·L⁻¹;

pH = 11.4; pOH = 2.6

Explanation:

The chemical equation is

For simplicity, let's re-write this as

1. Calculate [OH]⁻

(a) Set up an ICE table.  

   B + H₂O ⇌ BH⁺ + OH⁻

0.310               0        0

   -x                  +x      +x

0.310-x               x        x

Check for negligibility:

(b) Solve for [OH⁻]

2. Calculate the pOH

3. Calculate the pH

4 Calculate [H₃O⁺]

answer: -

reaction:

na + cl ⇌ nacl

balanced chemical equation:

na + 2cl ⇌ nacl2

sodium + clorine goes to form sodium chloride (table salt).

the product is nacl2.

and the reactants are na and cl.

(note: if you don’t know what ⇌ means, read below: -

⇌(double head arrow) means reversible reaction).