# Homework Help: Most plentiful no of particles in the solution?

1. Jun 17, 2012

1. The problem statement, all variables and given/known data
Name all the particles present in 2M nitric acid.Underline the name(s) of the most plentiful particles(apart from water molecules)

2. Relevant equations

3. The attempt at a solution
model answer:Water molecules,hydrated hydrogen ions,nitrate ions,hydrated hydroxide ions.
Could anyone tell me why the number of hydrated hydrogen ions and nitrate ions in the solution are equal?

equation 1:
HNO3(l) + H2O(l) --> H+(aq) + NO3-(aq)

equation 2:
H2O(l) --> H+(aq) +OH-(aq) (Note:most of the water molecules are not ionized)
(ignore)<--

Combining both cases,the no of H+(aq) should be greater than the no of NO3-(aq).
What's wrong?

thx so much ))))

2. Jun 17, 2012

### Staff: Mentor

Nothing is wrong, you are right - concentration of H+ is slightly higher than the concentration of NO3-. This is especially visible in the case of very diluted solutions. But in "normal" solutions difference is negligible - when the concentration of the acid is higher than 7*10-6M , difference in concentrations between H+ and NO3- is below 0.015%.

Last edited: Jun 17, 2012
3. Jun 17, 2012

thanks=]

4. Jun 17, 2012

sorry,there is still a question
Name all the particles present in 1M aqueous ammonia solution.Underline the name(s) of the most plentiful particles(apart from water molecules)
Is it possible for us to delete the word "aqueous" in "aqueous ammonia solution"?
aqueous ammonia solution = ammonia solution?

5. Jun 17, 2012

### Staff: Mentor

Water is not the only solvent in which you can dissolve ammonia. It is the most popular one, but you can try to dissolve ammonia in any other liquid.