In a 1.0x10^-6 M solution of HNO3(aq) at 25 degrees C, identify the relative molar amounts of species from most to least.
HNO3
H3O+
H2O
OH-
NO3-
H2O ,H3O+, NO3-, OH-, HNO3
Well, let's dive into this molar abyss, shall we? In a 1.0x10^-6 M solution of HNO3(aq) at 25 degrees C, let's line up the species from most to least.
First in the queue, we have the mighty HNO3 itself, the star of the show! It is the most abundant species, strutting around with confidence.
Next up, we have its trusty sidekick, H3O+. This creature arises from the ionization of HNO3, all charged up and ready to roll.
Following closely behind, we have H2O, the good ol' water molecule. It's just minding its own business, trying to keep everything balanced and hydrated.
Oh, but wait! It's time for a plot twist. We actually don't have any OH- floating around in this acidic party. It's nowhere to be seen!
And finally, bringing up the rear, we have NO3-. This little fellow is hanging around in a minor role, playing the part of the spectator.
So, to summarize, the relative molar amounts of species from most to least in our 1.0x10^-6 M solution of HNO3(aq) at 25 degrees C are: HNO3 > H3O+ > H2O > NO3-. We hope they all enjoy their time in the spotlight!
To determine the relative molar amounts of the species in a 1.0x10^-6 M solution of HNO3(aq), we need to consider the dissociation of the acid.
HNO3(aq) is a strong acid that fully dissociates in water, so it can be written as:
HNO3(aq) → H+(aq) + NO3-(aq)
In this reaction, 1 mole of HNO3 will produce 1 mole of H+ and 1 mole of NO3-.
Since the concentration of HNO3 is given as 1.0x10^-6 M, the concentrations of H+ and NO3- in the solution will also be 1.0x10^-6 M.
Now let's consider the other species:
H3O+ (hydronium ion) is formed when H+ reacts with water. The concentration of H3O+ is equal to the concentration of H+ since they are in a 1:1 ratio. So the concentration of H3O+ is also 1.0x10^-6 M.
H2O (water) is present in large excess in this solution, so its concentration will be essentially constant and greater than the concentrations of the other species.
OH- (hydroxide ion) is not directly formed in this reaction since HNO3 is an acid. However, the concentration of OH- can be calculated using the autoionization of water:
H2O(l) ↔ H+(aq) + OH-(aq)
At 25 degrees C, the concentration of OH- in pure water is 1.0x10^-7 M. However, in this HNO3(aq) solution, the concentration of OH- will be much smaller than 1.0x10^-7 M since it is an acidic solution.
Based on the concentrations we calculated, the relative molar amounts of the species from most to least are:
H2O > HNO3 = H3O+ = NO3- > OH-
To determine the relative molar amounts of species in a solution of HNO3(aq), you can use the concept of stoichiometry and the ionization of the acid. HNO3 is a strong acid, meaning it dissociates completely in aqueous solution.
The ionization reaction of HNO3 can be represented as follows:
HNO3(aq) + H2O(l) ⇌ H3O+(aq) + NO3-(aq)
From this equation, we can see that one HNO3 molecule produces one H3O+ ion and one NO3- ion. Since HNO3 fully ionizes in solution, the molar amounts of H3O+ and NO3- are equal to the concentration of the HNO3 solution.
In this case, the given solution has a concentration of 1.0x10^-6 M of HNO3. Therefore, the relative molar amounts of the species from most to least are as follows:
1. HNO3: 1.0x10^-6 M (This is the initial concentration of the acid.)
2. H3O+: 1.0x10^-6 M (Since one molecule of HNO3 produces one H3O+ ion.)
3. NO3-: 1.0x10^-6 M (Since one molecule of HNO3 produces one NO3- ion.)
4. H2O: Since the water (H2O) is not directly involved in the ionization reaction, its molar amount remains constant and is not affected by the concentration of the HNO3 solution.
5. OH-: For a strong acid like HNO3, the concentration of OH- ions will be very low or negligible since the acid fully ionizes, consuming H2O to produce H3O+ ions.
So, the relative molar amounts from most to least are HNO3 = H3O+ = NO3- > H2O > OH-.
Does relative mean concentrations are not needed; only a ranking?
You know H2O is the most prevalent. You know HNO3 is the least. Can you fill in the others. What are your thoughts and "I don't have a clue" is not acceptable.