Periodic Table Scientists

Front

What is the atomic mass?

Back

The atomic mass is the weighted average mass of an element's isotopes, measured in atomic mass units (amu). It is usually found at the bottom of each square on the periodic table.

Front

Who proposed the atomic theory that all matter is made up of atoms?

Back

John Dalton proposed the atomic theory, stating that all matter is composed of small particles called atoms.

Front

Who is known for creating the modern periodic table based on atomic number?

Back

Henry G.J. Mosely is known for creating the modern periodic table based on atomic number.

Front

What is the chemical symbol for Lithium?

Back

The chemical symbol for Lithium is Li.

Front

Which group of elements is stored in oil to prevent reactions with air?

Back

Alkali Metals are stored in oil to prevent reactions with oxygen and water in the air.

Front

What is the atomic number?

Back

The atomic number is the number of protons in the nucleus of an atom, which determines the element's identity.

Front

What are isotopes?

Back

Isotopes are variants of a particular chemical element that have the same number of protons but different numbers of neutrons.

Front

What is the significance of the periodic table?

Back

The periodic table organizes elements based on their atomic number, electron configuration, and recurring chemical properties.

Front

Who discovered the electron?

Back

J.J. Thomson discovered the electron in 1897.

Front

What are noble gases?

Back

Noble gases are a group of elements in Group 18 of the periodic table that are known for their lack of reactivity due to having a full valence shell.