NAT MCQs

Effective nuclear charge generally increases across a period.
Electrons are therefore harder to remove, with some exceptions.

Valence electrons are farther from the nucleus and more shielded down a group.
They are generally easier to remove.

Forming Na+ removes the outer 3s electron.
The cation is smaller than the neutral atom.

Adding an electron increases electron-electron repulsion.
The anion is larger than the neutral atom.

Ionic bonding follows electron transfer and ion formation.
The resulting cations and anions attract in a lattice.

Covalent bonds commonly form between nonmetal atoms.
Shared electrons are attracted to both nuclei.

Metallic bonding explains conductivity and malleability.
Valence electrons move through the metal lattice.

Bond polarity arises from electronegativity differences.
The more electronegative atom gains partial negative charge.

Identical atoms form nonpolar covalent bonds.
Small electronegativity differences also give nearly nonpolar bonds.

After formation, a coordinate bond behaves like an ordinary covalent bond.
The electron-pair donor provides both bonding electrons.

The octet rule is a useful main-group bonding guideline.
Hydrogen, boron, and expanded-valence species are exceptions.

Lewis structures use lines and dots for bonds and lone pairs.
They help predict connectivity and formal charge.