Module 2.2 Flashcards
What is an orbital
a region of space where one might find up to two electrons with opposite spins
what is ionic bonding
the electrostatic attraction between position and negative ions
what is covalent bonding
the strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms
what is relative atomic mass
the weighted mean mass of an atom of an element compared with 1/12 of the mass of carbon-12
what is relative isotopic mass
the mean mass of an atom of an isotope compared with 1/12 of the mass of carbon-12
what is empirical formula
simplest whole number ratio of atoms in a substance
how do you calculate number of electrons in a shell
2n^2
how do electrons enter shells
at the lowest energy shell available
whats the shape and occurrence of s orbitals
spherical shape, one in every principal level
whats the shape and occurrence of p orbital
dumbbell shape, 3 in levels 2 upwards
whats the shape and occurrence of d orbital
various shapes, 5 in levels 3 upwards
whats the shape and occurrence of f orbital
various shapes, 7 in levels 4 upwards
what energy level is lower, 4s or 3d
4s
what two elements have different electronic configuration and how
chromium - fills 3d singularly then one in 4s
copper - fills 3d in pairs and one in 4s
how do you work out the electronic configuration of ions
take from the highest occupied orbital (4s before 3d)
what is a giant ionic lattice
oppositely charged ions held in a regular repeating 3D lattice by electrostatic attraction
properties of ionic compounds
very brittle, insoluable in non-polar solvents (polar solvents stabilise the separated ions because the delta+ atoms attract the the negative ions and vice versa), doesnt conduct as a solid as the ions are in a fixed position in the lattice, but does molten and the ions are free to move as the lattice structure is broken
what are the properties of simple covalent molecules
never conduct (no free ions or delocalised electrons), more soluable in organic solvents rather than water, low boiling point as intermolecular forces are always weak (get strong-ER as molecules get a larger surface area)