Question

the periodic table organizes elements by increasing number.

Explanation:

The periodic table is a fundamental tool in chemistry. It arranges elements based on their atomic number. The atomic number of an element is defined as the number of protons in the nucleus of an atom of that element. As we move from left to right across the periodic table, the atomic number of the elements increases. This systematic arrangement helps in understanding the properties (physical and chemical) of elements, as elements with similar properties tend to be grouped together in columns (groups) and rows (periods). For example, elements in Group 1 (alkali metals) have similar reactivity patterns due to having one valence electron, and as we move from hydrogen ($H$, atomic number 1) to helium ($He$, atomic number 2) and so on across the table, the atomic number is the key parameter for this organization.

Answer:

atomic