Unit 1: A1 Structure and bonding in applications in science Flashcards
What are electronic orbitals, and how are they arranged in the Aufbau principle?
Electronic orbitals: Regions around the nucleus where electrons are likely to be found (s, p, d, f).
Aufbau principle: Electrons fill the lowest energy orbitals first (e.g., 1s, 2s, 2p).
Summarise Bohr’s theory of atomic structure.
Electrons orbit the nucleus in fixed energy levels. Energy is absorbed or emitted when electrons move between levels.
What is ionic bonding?
A strong electrostatic attraction between oppositely charged ions formed by the transfer of electrons from a metal to a non-metal.
How do ionic radius and ionic charge affect the strength of ionic bonding?
Smaller ionic radius = stronger bonding (closer ions).
Greater ionic charge = stronger electrostatic attraction
Describe covalent bonding.
A strong electrostatic attraction between two nuclei and the shared pair(s) of electrons between them.
What are the differences between single, double, and dative covalent bonds?
Single bond: One shared pair of electrons.
Double bond: Two shared pairs of electrons.
Dative bond: Both electrons in the shared pair come from one atom
What is metallic bonding?
A strong attraction between delocalized electrons and positive metal ions in a regular layer structure.
What are the three types of intermolecular forces?
Van der Waals: Weak forces from temporary dipoles.
Dipole-dipole: Attraction between permanent dipoles.
Hydrogen bonding: Strong attraction involving H bonded to F, O, or N
Define relative atomic mass and moles.
Relative atomic mass (Ar): Weighted average mass of an atom compared to 1/12th of carbon-12.
Mole: Amount of substance containing
Relative atomic mass (Ar): Weighted average mass of an atom compared to 1/12th of carbon-12.
Mole: Amount of substance containing
Relative atomic mass (Ar): Weighted average mass of an atom compared to 1/12th of carbon-12.
Mole: Amount of substance containing
6.022 × 10^23
What is the formula for percentage yield?
What are the key features of a cation and an anion?
Cation: Positively charged ion formed by electron loss.
Anion: Negatively charged ion formed by electron gain.
How are dot and cross diagrams used in covalent bonding?
They represent the sharing of electrons between atoms, using dots for one atom’s electrons and crosses for the other’s.
What is the relationship between bond length and bond strength in covalent bonds?
Shorter bond length = stronger bond (more shared electrons = stronger attraction).
Longer bond length = weaker bond.
Why is the tetrahedral structure important in organic chemistry?
It is the basis for the shapes of many molecules, especially those involving carbon with four single bonds (e.g., methane, CH₄).
What does the term “delocalized electrons” mean in metallic bonding?
Electrons that are free to move throughout the metal lattice, contributing to electrical and thermal conductivity.
How is molarity (concentration) calculated?
What is the formula for calculating moles from mass and molar mass?
