2007-12-16 18:48:48 · 6 answers · asked by mit 1 in Science & Mathematics ➔ Chemistry
The IONIC BOND results as a balance between the force of attraction between opposite plus and minus charges of the ions and the force of repulsion between similar negative charges in the electron clouds. In crystalline compounds this net balance of forces is called the LATTICE ENERGY. Lattice energy is the energy released in the formation of an ionic compound.
All ionic compounds, and therefore most solids, are crystals. That is, they consist of a regular, infinitely repeated array of anions and cations: a crystal structure. The arrangement of this crystal structure is not the same for all ionic compounds; rather, it varies depending on the nature (principally the size) of the ions which form the compound. The crystal structures of many ionic solids can be rationalized into about eight principal types.
The actual structure adopted by a particular compound depends principally on the relative sizes of the ions. If the anions and cations have very different sizes, it will be possible to fit one into the holes in the close-packed arrangement of the other, otherwise close-packing may not be possible. On the other hand, there is a considerable degree of variation, in some cases even in the same compound.
2007-12-18 19:22:50 · answer #1 · answered by sb 7 · 0⤊ 0⤋
Ionic compounds are basically defined as being compounds where two or more ions are held next to each other by electrical attraction. One of the ions has a positive charge (called a "cation") and the other has a negative charge ("anion"). Cations are usually metal atoms and anions are either nonmetals or polyatomic ions (ions with more than one atom). Think back to grade school: The same thing that makes the positive and negative ends of a magnet stick to each other is what makes cations and anions stick to each other.
Usually, when we have ionic compounds, they form large crystals that you can see with the naked eye. Table salt is one example of this - if you look at a crystal of salt, chances are you'll be able to see that it looks like a little cube. This is because salt likes to stack in little cube-shaped blocks.
Sometimes when you see a salt, it looks like a powder instead of a cube. This doesn't mean that the salt is not a crystal - it means that the crystals are just so small that you can't see them with the naked eye. If you were to put the powder under a microscope, chances are that you would see little geometric bloc
2007-12-19 00:15:29 · answer #2 · answered by Natasha 2 · 0⤊ 0⤋
All kinds of crystal structure are possible for ionic compounds, depending on the shape of the ions,, and their relative number. But the guiding principle is always that the ions are attracted to opposite charges, and repelled by the same charge. This gives rise to regular crystalline arrays.
2007-12-17 12:57:14 · answer #3 · answered by Facts Matter 7 · 0⤊ 0⤋
as their bonds are ionic(by loose or gain of electrons), it is very strong to break.. and hence they form solids. i.e. crystalline
2007-12-20 09:12:16 · answer #4 · answered by rk 2 · 0⤊ 0⤋
1.It is having face centre cubic form
2.electro valance of anion and cation are same.
2007-12-17 03:46:38 · answer #5 · answered by jayaraman s 1 · 0⤊ 0⤋
well lattice energy in space determines it
2007-12-17 06:37:50 · answer #6 · answered by raja 2 · 0⤊ 0⤋