The modern periodic table
In the modern periodic table:
- elements are arranged in rows, called A horizontal row in the periodic table., in order of increasing The number of protons in the nucleus of an atom. Also called the proton number.
- elements with similar properties are placed in vertical columns, called A vertical column in the periodic table containing elements with similar chemical properties.
- elements in the same group have the same number of electrons in their outer shell (this is what gives them similar properties)
The table is called the periodic table because elements with similar properties occur at regular intervals.
The modern periodic table with some elements left out for simplicity
Remember that the periodic table only lists elements, so you won't find compounds (eg water) or An alloy is a mixture of two or more elements, at least one of which is a metal., eg bronze listed there.