The Structure of an Atom and the Periodic Table

These flashcards cover essential concepts regarding the structure of atoms, isotopes, the periodic table, and the development of atomic theory.

What are the three primary particles of an atom?

Protons, neutrons, and electrons.

What is the atomic number?

The number of protons in an atom.

What is the mass number?

The sum of the number of protons and neutrons in an atom.

What is an isotope?

Atoms of the same element having different numbers of neutrons.

What is the key concept of Dalton's atomic theory?

All matter consists of tiny particles called atoms.

According to the Bohr theory, where do electrons exist?

In fixed energy levels surrounding the nucleus.

What is the principle behind electron configuration?

Electrons fill the lowest-energy orbital that is available first.

How do metals behave in terms of electrons?

Metals tend to lose electrons during chemical changes.

What is the octet rule?

Elements react to achieve a full complement of valence electrons, typically 8, like noble gases.

What is ionization energy?

The energy required to remove an electron from an isolated atom.

What happens to the size of an atom as you move across a period?

The size of an atom decreases.

What are valence electrons?

The outermost electrons in an atom that participate in bonding.

What is the significance of the periodic table?

It organizes elements based on their atomic number and properties.

What is the definition of a cation?

A positively charged ion formed by the loss of electrons.

What is an anion?

A negatively charged ion formed by the gain of electrons.