How can i know the valency of a compond to react it with another elemet to form a chemical reaction?
For example - Suppose I have to make . Then i have to first react Carbon with Oxygen then react that compond with calcium. So how will i know the valency of compound formed from reaction of carbon with oxygen. We can know the valency of elements from their atomic number and electronic configuration, but how can i know the valency of compound?
Please help,waiting for your reply,