At show clearly how bonding occured in (cao)
Calcium
oxide

They both combine with The help of valency, which is the combining capacity of elements

Explanation:

I find it easier to understand valency as part of the Bhor’s model of an atom.

In his model, it was stated that electrons are spread around the nucleus in such a way that there are rings around the model. Each ring has a n value. So, k has 1, l has 2, m has 3 and n has 4...

what you need to know to find the number of electrons in each ring is to solve the formula 2n squared

Then, the valency is the 8 minus the number of electrons in the outermost shell. Remember that 8 is max number I;outer most shell. If you try it out for oxygen, you will get the value of 2 remaining, which can be gained if combined with calcium.

Hope it helps

the number of protons in the nucleus of a given element. has slight luster and conducts electricity at high temperatures like metal.but like a nonmetal,boron is brittle and does not conduct electricity well at low temperatures. in graphite, carbon is a soft,brittle solid.it is reflective,ductile,or malleable.

it should have an internal chamber and two thermometers sticking out of the top. the internal chamber will also be closed off from the outside.