would the pH of a solution made by dissolving the following solds in water be less than 7, be equal to 7 or be greater than 7? explain
a) NaF (b) NaCl (c) AlCl3.... How do you figure this out? do you use the periodic table?
2007-02-07 17:43:46 · 3 answers · asked by jyoti b 1 in Science & Mathematics ➔ Chemistry
I partially disagree with the above person. NaF will form a basic solution. F- is the conjugate base of HF (hydrofluoric acid), which is a WEAK acid, not a strong one. Since it is VERY weak, the conjugate base would be somewhat strong. Thus, NaF will dissociate to Na+ and F-, but the F- will react with H20 to form HF and OH-, which makes the solution basic. Imagine this. H-F is so weak that it doesn't want to split but wants to be together, so if you have H and F, they will combine. As for NaCl, I agree with the other person. Cl- is the conjugate base of a strong acid (HCl), which would make Cl- weak. If you think about it, if HCl pretty much completely dissociates, there not much driving force the other way.
As for AlCl3, because the Al3+ is a highly charged metal cation, it is a Lewis acid in water, since it can receive a pairs of electrons (from water), (Lewis bases donate electrons) In general, most highly charged cations (usually 3+) are Lewis acids. The alkali and alkaline earth metals are not Lewis acids. As for the other person's comment, I don't see how AlCl3 is derived from a strong acid and weak base. Cl- is the conjugate base of a strong acid, so it's a very weak base (negligible pH). I don't get the other part.
2007-02-07 18:13:54 · answer #1 · answered by nebulastar 2 · 0⤊ 0⤋
NaF, NaCl have a Ph =7. There are salts of strong base and strong acid and should be dissociated and neutral
Al Cl3 is slightly acidic since Cl iderives from a strong acid and aluminium gives rise to a weak base
Look the link
2007-02-07 17:52:26 · answer #2 · answered by maussy 7 · 0⤊ 0⤋
pH = -log(base 10)[H+] The 'p' comes from 'potenz', German for 'power' (as in the nth power of a number ... given, I suppose, that pH is related to the 'power of 10' of the concentration). And the 'H' from the symbol for hydrogen. pH below 7 is an acidic solution; pH of 7 is neutral; and above 7 is basic.
2016-05-24 05:47:17 · answer #3 · answered by Maria 4 · 0⤊ 0⤋