hihi

[QuarkQuarkQuark2001]

Hihi I am a new member.

I want to ask about ,does the bond in HF is ionic bond?

[aommaster]

Nope, its a covalent bond. It gets complicated because a hydrogen atom can give one electron, and a fluorine atom can take an electron. The problem is that if a hydrogen atom gives the electron, it would become a nuclues with no protons. Thus, it forms a covalent bond

[QuarkQuarkQuark2001]

Nope, its a covalent bond. It gets complicated because a hydrogen atom can give one electron, and a fluorine atom can take an electron. The problem is that if a hydrogen atom gives the electron, it would become a nuclues with no protons. Thus, it forms a covalent bond

 

 

What is polar covalent bond , covalent bond and ionic bond?

Does HF with the polar covalent bond because of the 2 non-metals?

[aommaster]

Well, I can tell you something about ionic and covalent bonds, but not really anything about polar covalent bonds.

 

Ionic bonds are formed when a metal and a non-metal react. One gives the electrons and one takes the electrons. This forms two charged atoms, which atrtact together. One is positive and one is negative. These are ions, and when they stick together, they form ionic bonds!

 

The covalent bond is something differet. This usually happens when too much energy has to be used to either give or take the electrons. So, in that case, they share the electrons. Also, it may happen when a hydrogen atom, like the example in the first post, would end up with no electrons.

 

They do his all to ge ta full outer shell, remember.

 

As for the other questions, I have no absolute idea

[budullewraagh]

sorry to disagree, aom, but i believe that the bond is considered ionic. ionic and polar covalent are subject to opinion, but the accepted difference between ionic and polar covalent is that an ionic bond is formed when the difference in electronegativity is 1.7 or greater, and if the difference is less than 1.7, then the bond is polar covalent.

electronegativity of H=2.2

electronegativity of F=4

4-2.2=1.8

1.8>1.7

therefore, the bond between H and F in the molecule HF is ionic.

 

i would like to add, however, that all ionic bonds are partially polar covalent, since it still IS a bond, and the H hasn't totally given up its electron. the H still has influence on the position of its "former" electron, since it is caught between the H and F nuclei in an SP hybrid orbital.

[aommaster]

Oh ok. As long as I am corrected, I have no problem at all

[yangxu]

sorry, just wondering... doesn't HF belong to hydrogen bond group? I thought hydrogen bonding is like a special type of bonding that doesn't belong to covalent or ionic bonding category... plus I think ionic means that you have to transfer your entire electron from one atom to another, but hydrogen bonding isn't something that obeys that rule...

[budullewraagh]

"hydrogen" bonding isn't a good name. "hydrogen" bonding is when an atom's nucleus (generally hydrogen's in organic molecules) is attracted to another atom's electrons. there is no actual bond, since electrons are not used in a hybrid orbital. still, the hydrogen "bond" has an effect on the stability of a molecule, since the bond between the H and something else is effected by the attraction of the H to other atoms.

[QuarkQuarkQuark2001]

"hydrogen" bonding isn't a good name. "hydrogen" bonding is when an atom's nucleus (generally hydrogen's in organic molecules) is attracted to another atom's electrons. there is no actual bond, since electrons are not used in a hybrid orbital. still, the hydrogen "bond" has an effect on the stability of a molecule, since the bond between the H and something else is effected by the attraction of the H to other atoms.

 

 

Do these kinds of knowledge are taught in physical chemistry>?

[YT2095]

sorry to disagree' date=' aom, but i believe that the bond is considered ionic. ionic and polar covalent are subject to opinion, but the accepted difference between ionic and polar covalent is that an ionic bond is formed when the difference in electronegativity is 1.7 or greater, and if the difference is less than 1.7, then the bond is polar covalent.

electronegativity of H=2.2

electronegativity of F=4

4-2.2=1.8

1.8>1.7

therefore, the bond between H and F in the molecule HF is ionic.

 

i would like to add, however, that all ionic bonds are partially polar covalent, since it still IS a bond, and the H hasn't totally given up its electron. the H still has influence on the position of its "former" electron, since it is caught between the H and F nuclei in an SP hybrid orbital.[/quote']

an excellent answer!

but if you`re using the Pauling scale, isn`t Hydrogen 2.1?

[aommaster]

Pauling scale? What's that?

[YT2095]

it`s an arbitrary scale set by a chap called Pauling" (as far as I know) and i`ts designed to set out the relative elecro-negativity of all known elements on a scale of 1 to 4

[aommaster]

Oh, that makes sense

[YT2095]

yeah, it is handy

but the only times it really isn`t enough is with the transitional metals, where you get a group of 4 metals all with the same number, and yet a displacement reaction can and does take place.

it`s fantastic for general work though

[aommaster]

Thanx YT!

[QuarkQuarkQuark2001]

sorry to disagree' date=' aom, but i believe that the bond is considered ionic. ionic and polar covalent are subject to opinion, but the accepted difference between ionic and polar covalent is that an ionic bond is formed when the difference in electronegativity is 1.7 or greater, and if the difference is less than 1.7, then the bond is polar covalent.

electronegativity of H=2.2

electronegativity of F=4

4-2.2=1.8

1.8>1.7

therefore, the bond between H and F in the molecule HF is ionic.

 

i would like to add, however, that [i']all ionic bonds are partially polar covalent[/i], since it still IS a bond, and the H hasn't totally given up its electron. the H still has influence on the position of its "former" electron, since it is caught between the H and F nuclei in an SP hybrid orbital.

 

 

Is "all ionic bonds are partially polar covalent" only for hydrogen bonds?

[budullewraagh]

Is "all ionic bonds are partially polar covalent" only for hydrogen bonds?

 

i'll assume you're speaking of chemical bonds involving hydrogen as opposed to van der waal's forces. correct me if i'm wrong.

 

the statement that all ionic bonds are partially polar covalent covers all ionic bonds. hydrogen cannot make an "ionic" bond since its electronegativity is so high for a "cation".