- Elements are substances that cannot be broken down into anything simpler.
- Atoms are individual particles from which the element is made.
- Molecules are the pairs of individual atoms.
- Water is NOT an element but has molecules that are each built from one atom of oxygen and two atoms of hydrogen.
- Combinations of two or more different elements are called compounds.
- The recurrence of similar properties in the families is known as periodicity.
- The arrangement of elements is called the periodic table of elements.
THE PERIODIC TABLE
- The families in the periodic table are in vertical columns.
- noble gases= helium (He), neon (Ne) and argon (Ar).
- halogens= fluorine (Fl), chlorine (Cl), bromine (Br) and iodine (I).
- alkali metals= lithium (Li), sodium (Na)…