Its all there ^
2006-12-11 05:04:21 · 8 answers · asked by superscott789 1 in Science & Mathematics ➔ Chemistry
By definition, a solution is "acidic" when the pH value is lower than 7 (0-7) and basic, when the pH value is higher than 7 (7-14). The pH is derived from the log value of the number of moles of [H+] ions in a water solution (or more precisely of H3O+, which is the hydrated version of H+]. For example, if a solution is pH 1, it means that there are 10 exp(-1) moles of [H3O+] in the solution.
The sum of the negative value of the log of the [H3O+] ions + the negative value of the log of the [OH-] is always 14.
An acid, is a substance able to "loose" H+ ions with water by dissociation. For example HCl (hydrochloric acid), will dissociate in water into H+ (or H3O+) and Cl-, therefore it will decrease the pH of the water solution.
An alkaline compund, on the contrary, increases the concentration of [OH-] ions and therefore the pH of the solution.
Hope it makes sense!
2006-12-12 03:18:29 · answer #1 · answered by Jesus is my Savior 7 · 0⤊ 0⤋
Acid properties need the h+ ion to be dissociated. In water this is facilitated by formation of the hydroxonium ion h3o+ between one molecule of water and the h+ ion. This has a lower formation energy than h+ due to charge delocalisation.
2006-12-11 11:47:59 · answer #2 · answered by peter c 2 · 0⤊ 0⤋
The H+ ions can only dissociate from its molecule in the presence of water.
E.g. HCl will exist as a covalent molecule when it is a gas. In the presence of water, HCl ---> H+ + Cl- due to the polarising effect of water. The H+ formed is what makes the solution acidic.
2006-12-11 10:36:23 · answer #3 · answered by Kemmy 6 · 0⤊ 0⤋
Because the acidity is caused by hydrogen ions. The hydrogen ions cannot disassociate from the molecule unless there is a solvent such as water present.
2006-12-11 05:22:12 · answer #4 · answered by in vino veritas 4 · 0⤊ 0⤋
If there is no water present a substance cant demonstrate its acid qualities. See below for a proper explanation.
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2006-12-11 05:08:24 · answer #5 · answered by Anonymous · 0⤊ 0⤋
by using fact the acidity of a substance relies upon on it somewhat is skill to supply Hydronium ions. you're able to have been taught that the equilibrium of an acid replaced into right here: H2SO4 (Sulfuric acid) <=> HSO4- + H+ it somewhat is incorrect when you consider that protons are (below STP) by no potential loose yet continually linked to some thing. the ideal suited equilibrium is right here: H2SO4 + H2O <=> HSO4- + H3O+ (Hydronium)
2016-12-30 06:33:47 · answer #6 · answered by Anonymous · 0⤊ 0⤋
Acidity is caused by hydrogen ions, these are only available when dissolved in water.
2006-12-11 05:48:39 · answer #7 · answered by Gordon B 7 · 0⤊ 0⤋
as above
2006-12-11 05:14:26 · answer #8 · answered by dream theatre 7 · 0⤊ 0⤋