So it says (or my understanding of it is) when the pH level is 7 (neutral) in a solution, there is an equal amount of hydrogen and hyrdoxide ions.
And then when the pH level is 0-6, it's acidic, and there are more hydrogen ions than hydroxide ions.
And finally, when the pH level is 8-14, it's basic, and there are more hydroxide ions than hydrogen ions.
I looked at some of the examples provided... And for, say, an acidic solution, there aren't any hydroxide ions AT ALL? Since acids are compounds that produce hydrogen ions when dissolved in water, then would there be any hydroxide ions involved?
For example, HCl (aq) -> [H]+ plus [Cl]- (the + and - are the charges).
Also, what would H2SO4 (aq) be then? Can you put it the same way as above (like, H2SO4 -> [?] plus [?])?
Same with the basic solutions... So rather than there being more hydrogen ions, it seems that there are just no hydroxide ions at all?
I feel like I'm just missing something obvious here...
I feel really stupid asking this question, but my teacher is just really bad at teaching and I don't get her at all...
And then when the pH level is 0-6, it's acidic, and there are more hydrogen ions than hydroxide ions.
And finally, when the pH level is 8-14, it's basic, and there are more hydroxide ions than hydrogen ions.
I looked at some of the examples provided... And for, say, an acidic solution, there aren't any hydroxide ions AT ALL? Since acids are compounds that produce hydrogen ions when dissolved in water, then would there be any hydroxide ions involved?
For example, HCl (aq) -> [H]+ plus [Cl]- (the + and - are the charges).
Also, what would H2SO4 (aq) be then? Can you put it the same way as above (like, H2SO4 -> [?] plus [?])?
Same with the basic solutions... So rather than there being more hydrogen ions, it seems that there are just no hydroxide ions at all?
I feel like I'm just missing something obvious here...
I feel really stupid asking this question, but my teacher is just really bad at teaching and I don't get her at all...
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Everything you said in your first paragraph is correct. Your teacher isn't THAT BAD, and you have been paying attention.
Let's start with pure water. It used to be thought that pure water didn't have any H+ or OH- ions. As more and more sensitive instruments and mathematics came into being it was discovered that pure water did indeed have H= and OH- but in very small concentrations. As a matter of fact the concentration of both ions in pure water is 1.0 x 10^-7. Very small indeed.
Now consider the equation for the dissociation of water H2O <-------------> H+ + OH-
Notice that the arrow goes both ways? It is a REVERSIBLE reaction.
OK, Now consider what happens if you add an acid. A simple definition of an acid is that it is a substance that releases H+ ions in water. OK, so you add an acid to water, and a whole bunch of new H+ ions are released. What will Happen? Well can you see from the equation that H+ does react with OH- ions to produce water IN THE REVERSE DIRECTION!!. So when you add an acid to water the H+ ions will react with any OH- ions in the water to produce water. The concentration of OH- ions goes down significantly as the concentration of H+ goes up. The reverse happens when you add a base to water to release OH- ions. This a very simple explanation of what happens, but it helps to think of it that way. So the OH- ions never really disappear at all when you add an acid because the equation is REVERSIBLE. There will always be a few molecules of H2O breaking apart to release H+ and OH- ions.
Hope that helps.
Let's start with pure water. It used to be thought that pure water didn't have any H+ or OH- ions. As more and more sensitive instruments and mathematics came into being it was discovered that pure water did indeed have H= and OH- but in very small concentrations. As a matter of fact the concentration of both ions in pure water is 1.0 x 10^-7. Very small indeed.
Now consider the equation for the dissociation of water H2O <-------------> H+ + OH-
Notice that the arrow goes both ways? It is a REVERSIBLE reaction.
OK, Now consider what happens if you add an acid. A simple definition of an acid is that it is a substance that releases H+ ions in water. OK, so you add an acid to water, and a whole bunch of new H+ ions are released. What will Happen? Well can you see from the equation that H+ does react with OH- ions to produce water IN THE REVERSE DIRECTION!!. So when you add an acid to water the H+ ions will react with any OH- ions in the water to produce water. The concentration of OH- ions goes down significantly as the concentration of H+ goes up. The reverse happens when you add a base to water to release OH- ions. This a very simple explanation of what happens, but it helps to think of it that way. So the OH- ions never really disappear at all when you add an acid because the equation is REVERSIBLE. There will always be a few molecules of H2O breaking apart to release H+ and OH- ions.
Hope that helps.