Since this atom has a total of eight electrons ... After the third energy level has 8 electrons, the next electron goes into the fourth level. 4th Period: Potassium and Calcium—Electrons go into the ...

So, today we're going to look at the periodic table. That thing that you see behind ... For example, lithium (Li), sodium (Na) and potassium (K) all have the same kind of reaction with water.

Each element in the periodic table has: A unique symbol – a one or two-letter abbreviation used to represent the element. An ...

Our bodies require other elements, including non-metal elements such as phosphorus (P), sulphur (S) and chlorine (Cl), and metal elements like potassium ... of the periodic table and are mainly ...

So, today we're going to look at the periodic table. That thing that you see behind ... For example, lithium (Li), sodium (Na) and potassium (K) all have the same kind of reaction with water.