Because they are more in close proximity to the core atom's nucleus than lone pairs are, lone pairs reject other lone pairs more strongly than bonding pairs do effect the bond angle.
When a single pair of electrons at the central atom begins to resist the bound pair of electrons, the bond angle decreases and the bonds are slightly shifted inward. It moves existing atoms closer together and modifies their geometry. It's equivalent to include an atom. When there is an increase in back bonding, the bond angle rises. Because the lone pair electrons of the two atoms reject one another, adjacent atoms in a molecule that have lone pair electrons will not be kept together in their bond as securely.
Look up the relative atomic mass of . , and on a modern periodic table:
: .
: .
: .
The ionic compound consist of magnesium ions and sulfite ions .
Notice that and combine at a one-to-one ratio to form the neural compound . Therefore, each formula unit would include one ion and one ion (that would be two ions in total).
Calculate the formula mass of one such formula unit:
.
In other words, the mass of one mole of formula units (which includes one mole of ions and one mole of ions) would be .
Calculate the number of moles of such formula units in that of :
.
There are two moles of ions in each mole of formula units. Therefore, that of formula units would include approximately of ions.