★ Must-know
📌 The octet rule describes the tendency of an atom to gain 8 electrons in its valence shell, while the duplet rule applies to hydrogen and helium and involves 2 electrons.
Further detail
📌 When different atoms are present in the same number in a Lewis structure, the atom with the greater need for electrons is placed in the center; between carbon and nitrogen, nitrogen has 5 valence electrons and carbon has 4.
Octet seeks 8 electrons, whereas duplet seeks 2.
1. Regarding Lewis structures and valence rules, which propositions are correct?
2. Concerning chemical bonds and molecular structures, which propositions are correct?
3. Which molecular structures and bonding descriptions are accurate?
What is a chemical bond?
The force of attraction holding atoms together in a compound.
What does the octet rule describe?
An atom's tendency to gain 8 electrons in its valence shell.
What electronegativity difference characterizes a non-polar covalent bond?
A small electronegativity difference.
What is the Lewis structure of hydrogen cyanide?
H–C≡N with a single H–C bond and a triple C≡N bond.
Chemical bond
Force of attraction holding atoms together.
Ionic bond
Electron transfer creates charged ions.
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