Exploring Atomic Structure and Trends

What is the atomic number of an element?

• The atomic number is the number of neutrons in the nucleus.

• The atomic number represents the mass of an element.

• The atomic number of an element is the number of protons in its nucleus.

• The atomic number is the total number of electrons in an atom.

How is the atomic mass of an element calculated?

• The atomic mass is the sum of protons and neutrons only.

• The atomic mass is determined by the most abundant isotope.

• The atomic mass is the weighted average of the masses of an element's isotopes.

• The atomic mass is a fixed value for all elements regardless of isotopes.

What does the electron configuration of an atom represent?

• The number of protons in an atom.

• The distribution of electrons in an atom's orbitals.

• The energy levels of an atom's electrons.

• The mass of an atom's nucleus.

How many electrons can the first shell of an atom hold?

• 1

• 10

• 8

• 2

What is the significance of the periodic table's groups?

• They represent the atomic mass of elements.

• They show the number of protons in each element.

• The significance of the periodic table's groups is that they indicate elements with similar chemical properties.

• They categorize elements based on their physical state.

How do atomic radii change across a period?

• Atomic radii increase across a period.

• Atomic radii fluctuate randomly across a period.

• Atomic radii remain constant across a period.

• Atomic radii decrease across a period.

What trend is observed in ionization energy down a group?

• Ionization energy increases down a group.

• Ionization energy decreases down a group.

• Ionization energy fluctuates down a group.

• Ionization energy remains constant down a group.

What is the electron configuration for oxygen?

• 1s² 2s² 2p³

• 1s² 2s² 2p²

• 1s² 2s² 2p⁶

• 1s² 2s² 2p⁴

How does electronegativity vary across the periodic table?

• Electronegativity remains constant across a period and down a group.

• Electronegativity increases down a group and decreases across a period.

• Electronegativity increases across a period and decreases down a group.

• Electronegativity decreases across a period and increases down a group.

What are the characteristics of alkali metals?

• Alkali metals have a full outer shell of electrons.

• Alkali metals are non-reactive and have high density.

• Alkali metals are highly reactive, have low density, low melting and boiling points, and possess one electron in their outer shell.

• Alkali metals are solid at room temperature and have high melting points.