Bonding and shapes

Question 1

Metallic structure and bonding

Answer 1

• Strong electrostatic attraction between positive metal ions and negative delocalized electrons.
  Comparing strengths of bonding: Mg and Na
  Mg stronger because has a greater charge of 2+, has twice as many electrons. Stronger electrostatic attraction.
  All metals are good thermal and electrical conductors. - delocalized electrons help to transfer energy through the metal efficiently.
  Very strong due to strong electrostatic attraction.
  metals are malleable and ductile because layers of ions can slide over one and other

Question 2

Covalent bond

Answer 2

Definition: Shared pair of electrons between two atoms.
Macromolecules: C, Si, SiO- diamond and graphite.

Question 3

Simple molecular

Answer 3

Diatomic molecules with simple covalent bonds

Question 4

Ionic bonding and structure

Answer 4

Strong electrostatic attraction between oppositely charged ions.
High melting and boiling points, good electrical conductivity. Brittle and shatter easily

Question 5

Coordinate bond

Answer 5

Shared pair of electrons which have both come from the same atom. Always represented by an –>, points to the atom that donates the electron pair.

Question 6

Repulsion strengths

Answer 6

Lone pair lone pair> Lone pair to bonding pair> bond pair to bond pair.

Question 7

Electronegativity

Answer 7

Power of an atom to attract a pair of electrons in a covalent bond. factors that effect it- Nuclear charge, atomic radius, the shielding. Closer an element to F to more electronegative it is. Across p2 electronegativity increases beacuse: Number of protons increase, shielding remains the same. ability to attract electrons in a covalent bond increases.

Question 8

Polarity

Answer 8

The atom with the greater amount of electron density is given a d- and the atom with the less electron density is given a d+.

Question 9

Hydrogen Bonding: H-F, H-O, H-N

Answer 9

Arises by very large difference in electronegativity between atom 1 and atom 2. Creates a dipole in the Atom 1-atom 2 bond. Lone pair on atom 1 in one molecule is strongly attracted to a partially positive atom 2 on a different molecule.

Question 10

permeant dipoles

Answer 10

Weaker than H bonding, occurs between polar molecules.
Arises: Difference in electronegativity leads to bond polarity, Dipoles don’t cancel out therefore has n overall permanent dipole. Attraction between d+ on one molecule and d- on the other.

Question 11

IDD

Answer 11

Weakest IMF, occurs between all molecules (non-polar)
Arises: random movement of electrons leads to an uneven distribution of electrons, creating a temporary dipole in one molecule. This induces a dipole in another molecule, dipoles attract.