How do you tell how many electrons are in the outer layer of an element?

Answer 1

The outermost principal shell -or regions around the nucleus where electrons move- contains the valence electrons. The number of valance electrons can be calculated for the columns with A's above them. The number given to the column represents the number of valence electrons (written before and next to the A). For instance, Lithium (Li) and Sodium (Na) have one valence electron because they are in column one. During chemical bonding, these two elements and others in their column have the same configuration of outer electrons; thus, they tend to lose their single electron in order to gain a full outer shell. Similarly, oxygen (O) and sulfur (S) have 6 valence electrons, so they tend to gain electrons to make their full outer shell.

Answer 2

well they go like this (by the way this is grade 9 science so yeahmight be different for others) OKAY it is: 2,8,8,18,18,32,32 hope that helps =)

Answer 3

You can tell how many electrons are in the outer shell of an atom by looking at what group it is in as the group number is the same as the number of electrons in the outer shell.