As you move from left to right across the periodic table ... of the filled inner electron levels. These electrons screen or shield the outer electrons from the nuclear charge.

The “lead” of a pencil is actually made of a substance called graphite which is made of carbon atoms. The picture shows a close-up of one carbon atom. A hydrogen atom has one proton as the nucleus and ...

Some elements in the periodic table, such as carbon ... The "spare" electron from each dopant atom acts like a negative charge, so semiconductors of this type are called negative-type or N ...