Why does HCl dissolve?

[eleco]

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Why does HCl dissolve in water if Cl is a more electro negative element that O?

[Casmira]

Doesn't Cl become a negative ion and float between The hydrogen end of water?

[nick1048]

like disolves like...

[eleco]

Originally Posted by Casmira

Doesn't Cl become a negative ion and float between The hydrogen end of water?

But how does oxygen rip the H+ ion or proton of Cl if its a less electronegative element

[xiao1985]

dissolve as in a physical phenomenon, where intermolecular forces are overcome or the fact that HCl ionises and hence becoming H + and Cl -?!?! if tis the latter then water does too to a small extent...

[eleco]

Originally Posted by xiao1985

dissolve as in a physical phenomenon, where intermolecular forces are overcome or the fact that HCl ionises and hence becoming H + and Cl -?!?! if tis the latter then water does too to a small extent...

explain, why is it ionised if oxygen is less electro negative, why wouldnt Cl have a stronger attraction to its proton (H+ ion)

[t-i-m-m-y]

Originally Posted by eleco

explain, why is it ionised if oxygen is less electro negative

I was under the impression oxygen is the second most electronegative element, besides flourine.. which would make sense

the oxygen is feelin' real EN, so its greedy and attracts the H+.. thus 'pulling' apart the HCl, leaving H+ and Cl-

[april____]

Doesn't HCl just dissolve in water to make it a less concentrated acid.
I don't really think that you need to understand why it happens... just that it does.
Remember water is polar.

[xiao1985]

ok if HCl is an ionic lattice for a start, then the dissolution of it not only depend on pullin strength, also the enthalpy of of the solid...

and remember, whilst it is experiencing attracting from the negatively charged Cl -, it also experience repulsion from other H + ions in the lattice...

in addition, at most only 3 Cl - ions can be adjacent to an H + ion on the corner of the lattice, where as it is possible for more than 3 oxygen atoms to exert a force on hydrogen ion...

[~*HSC 4 life*~]

this covers a bit of preliminary chem...firstly, HCl is a covalent molecular compound, because H and Cl have different electronegativities, a unequal sharing of electron pairs results. Cl is more lectronegative than H .: has a better ability to attract the shared pair of electrons towards itself, causing one end of the molecule to become slightly negative, and the other hydrogen end slightly positive- now, this is known as a polar covalent bond. As we know, water is also a polar molecule (due to oxygen having abetter ability to draw electrons towards itself making a partial negative charge aroudn the oxygen and a partial pos charge around hydrogen thus causing the molecule to become "bent") Because of the polar nature of water, we can understand why it is 'the universal solvent' in the sense that it can dissolve other things due to interactions between charges (including things like dipoles and ions) So when Hcl and water are mixed, the dipoles of each molecule orientate themself so that pos and neg charges are aligned causing the solution to have a somewhat constant composition.

[Casmira]

See the first two terms of chemistry i never really paid much attention too because i was working 6 days a week, I should go over it again, I don't even remember what electronegativity easy@#$

[Casmira]

Originally Posted by theChemCoach

this is an excellent question, to which the answer lies in any first year chemistry textbook, for those that want to look it up.

Remember, chlorine DOES have a higher EN value than oxygen, and HCl does NOT exist as an ionic lattic, this type of structual bonding only exist in solids, so far i havent encountered HCl(s), HCl in its 'natural' state is a gas and dissolved in water, acts like an acid.

Keep at this one, i'll post answer eventually


Best of Luck

my teacher was telling me that, because dissolving HCl in water free's Hydrogen ions, and as we all know solution with H+ ions is likely to be an acid

[~*HSC 4 life*~]

Originally Posted by Casmira

See the first two terms of chemistry i never really paid much attention too because i was working 6 days a week, I should go over it again, I don't even remember what electronegativity easy@#$

electronegativity in simple terms is how badly something wants electrons eg Cl having 7 electrons in its valence shell has a strong electronegativity (really wants that one electron to complete its shell). Don't worry if you forget some year 11 work, i sure did, but i strongly suggest you go back and continually revise the basics, because they are basics afterall and they are the foundation upon which you build your knowledge from the hsc course

[nit]

The oxygen atom has a higher EN than the chlorine atom (3.5 on the Pauling scale vs 3.0 for the chlorine atom). Firstly, this should be obvious, given that the chlorine atom is never part of any hydrogen bonding network (EN not high enough), and this relationship between O's EN anf Cl's EN can be rationalised by keeping in mind that chlorine occurs in the 2nd period of the periodic table, while oxygen is in the 1st and subsequently oxygen has a much smaller atomic radius and a greater effective nuclear charge Z.

[t-i-m-m-y]

Originally Posted by nit

The oxygen atom has a higher EN than the chlorine atom (3.5 on the Pauling scale vs 3.0 for the chlorine atom).

That's what I thought.. but chemcoach says Cl > O (in terms of EN)