Ionic bonding (1 Viewer)

[Forbidden.]

The ionic bond forms between two elements, one with a small number of electrons in the valence shell (metal) and one with an almsot full outershell (non-metal). Sodium and chlorine form an ionic bond, with sodium giving up an electron from its valence shell and donating it to the chlorine atom to complete its valence shell.

The non metal atoms attract valence electrons from metal atoms to become negatively charged, eg, chlorine accepts an electron to become Cl^-. The metal atom releases electrons to become positively charged, eg, sodium loses an electron to become Na⁺.
These charged atoms (ions) are then held together by attraction of opposite charges creating an ionic bond between them.

Ionic bonds are not directional, because the bonding is created by opposite charges on the ions. This means the ions have freedom in the way that they pack. however, ions of opposite sign must surround each other to retain the attraction between ions.

Ionic bonds are strong and stiff. As a result they generally give a material high strength, high elastic modulus, high melting point and poor electrical conductivity.
Ionic bonding is the dominant bonding in some ceramics such as magnesia (MgO), alumina (Al₂O₃) and cement.


Copyright School of Material Sciences and Engineering UNSW 2008

theshortykatt is a deformed slut

 

[jockrussell]

Dipole-Dipole attraction occurs between polar molecules. e.g water (H2O)
i drew a picture for u but its too big.

 

[lyounamu]

Dipole-Dipole attraction occurs between polar molecules. e.g water (H2O)
i drew a picture for u but its too big.

Water is actually bonded by a strong intermolecular forced called hydrogen bonding that is 1/10 of the strength of a normal covalent bond. It's similar to the dipole-dipole force but technically, hydrogen bonding is the right term.

 

[jockrussell]

ill draw it with letters
H(δ+)
(δ+)H H(δ+) (δ+) /
\ / H O(δ-)
O(δ-) / \
(δ+)H H(δ+)(δ-) O H(δ+)
\ / \
O(δ-) H(δ+)
O(δ-)
/ \
(δ+)H H(δ+)
O is more electronegative than H so it hogs more of the e- making it slightly neg and H slightly pos.
These slightly neg and pos charges attract making a water dropplet.

 

[jockrussell]

awww it didnt work

 

[minijumbuk]

Dipole-Dipole attraction occurs between polar molecules. e.g water (H2O)
i drew a picture for u but its too big.

It's not a good idea to associate dipole-dipole attraction forces with the intermolecular forces within H2O.
They have a different classification for 3 specific atoms which form "Hydrogen bondings" with H. These are the F, N, and O. They are given the term "H- bonding" because those 3 elements are the most electronegative elements on the periodic table, and hence, the intermolecular force holding them is consequently much higher. Technically, they are still dipole-dipole interaction forces, but they just give them a special name.

Dipole-dipole forces are just generally any interaction forces between molecules as a result of different electronegativities of two or more atoms in a covalent bond. They must be polar overall, but does not need to specify which element. E.g. you can have H2S, or CH2CHCl. As long as they are polar, they will have dipole-dipole forces between molecules.

 

[jockrussell]

It's not a good idea to associate dipole-dipole attraction forces with the intermolecular forces within H2O.
They have a different classification for 3 specific atoms which form "Hydrogen bondings" with H. These are the F, N, and O. They are given the term "H- bonding" because those 3 elements are the most electronegative elements on the periodic table, and hence, the intermolecular force holding them is consequently much higher. Technically, they are still dipole-dipole interaction forces, but they just give them a special name.

Dipole-dipole forces are just generally any interaction forces between molecules as a result of different electronegativities of two or more atoms in a covalent bond. They must be polar overall, but does not need to specify which element. E.g. you can have H2S, or CH2CHCl. As long as they are polar, they will have dipole-dipole forces between molecules.

Yea i no this i was just using it as an example as water is a small molecule which everybody knows.

 

[minijumbuk]

Why isn't it helping? What part did you not understand?

 

[Aerath]

You can't upload images from your computer. They need to be online at Imgshack or somewhere.

 

[jockrussell]

You can't upload images from your computer. They need to be online at Imgshack or somewhere.

Yea i found this out lol, but u can upload pictures that are less 97.7kb or less from ur computer. This is what it said when i was trying to upload mine but it was 1.6mb

 

[Continuum]

ill draw it with letters
H(δ+)
(δ+)H H(δ+) (δ+) /
\ / H O(δ-)
O(δ-) / \
(δ+)H H(δ+)(δ-) O H(δ+)
\ / \
O(δ-) H(δ+)
O(δ-)
/ \
(δ+)H H(δ+)
O is more electronegative than H so it hogs more of the e- making it slightly neg and H slightly pos.
These slightly neg and pos charges attract making a water dropplet.

Lol... I can't understand that diagram at all...

 

[Aerath]

Lol... I can't understand that diagram at all...

Actually, they do make sense...sorta. The poster used the space bar to move all the diagrams across, however, it didn't work, since BoS removes unecessary spaces.