Chemistry Atomic Structure

What is the smallest unit of an element that still retains the properties of that element?

• molecule

• atom

• nucleus

• cell

Who discovered the electron and what is its charge?

• Albert Einstein, -1.6 x 10^-19 C

• Isaac Newton, +1.6 x 10^-19 C

• J.J. Thomson, -1.6 x 10^-19 C

• Marie Curie, -1.6 x 10^-19 C

What is the atomic number of an element?

• Number of protons

• Number of neutrons

• Number of isotopes

• Number of electrons

Explain the difference between atomic mass and atomic number.

• Atomic mass is the total mass of an atom, while atomic number is the number of protons in the nucleus.

• Atomic mass is the weight of an atom, while atomic number is the weight of the nucleus.

• Atomic mass is the number of neutrons in the nucleus, while atomic number is the number of electrons in the atom.

• Atomic mass is the number of protons in the nucleus, while atomic number is the total mass of an atom.

What is an isotope?

• Atoms with different numbers of protons

• Different elements with the same number of neutrons

• Atoms of the same element with different numbers of neutrons.

• Molecules with varying electron configurations

Describe the structure of an atom according to the Bohr model.

• Atom has a central nucleus with protons and neutrons, surrounded by electrons in specific energy levels.

• Atom consists of a single energy level where all particles are located

• The nucleus of an atom is made up of electrons and protons

• Electrons are located outside the nucleus in a random pattern

What are valence electrons and why are they important?

• Valence electrons are the electrons in the outermost shell of an atom. They are important because they determine the chemical properties of an element, including how it will bond with other elements.

• Valence electrons have no impact on chemical reactions.

• Valence electrons are the electrons in the nucleus of an atom.

• Valence electrons are only found in metals.

How many electrons can each orbital hold in an atom?

• 8

• 2

• 6

• 4

What is the significance of the nucleus in an atom?

• It controls the movement of electrons within the atom.

• It determines the color of the atom.

• It is responsible for the atom's chemical reactivity.

• It contains protons and neutrons, which determine the element's identity and mass.

Explain the concept of electron configuration.

• Electron configuration refers to the arrangement of protons in an atom's nucleus.

• Electron configuration is the process of converting electrons into protons.

• Electron configuration is determined by the number of neutrons in an atom.

• Electron configuration is the arrangement of electrons in an atom's electron shells or energy levels based on the Aufbau principle, Pauli exclusion principle, and Hund's rule.