electronegativity and dipoles

• what is a pure covalent bond?

  between 2 atoms of same type

  electron density is shared symmetrically
• what is a polar covalent bond?

  not shared equally between 2 atoms

  one will attract shared pair of electrons more

  causes bond to be polarised
• what is electronegativity?

  power of an atom to attract the pair of electrons in covalent bond
• what is the order of electronegativity?

  most ------->least

  F O N Cl Br C H
• what is the trend of electronegativity down a group?

  decreases
• what is the trend of electronegativity along a period?

  increases
• which atom attracts electron pair more in covalent bond?

  most electronegative atom
• what is a permanent dipole?

  molecules with polar bond have it
• which atom is partially negative?

  more electronegative
• which atom is partially positive?

  less electronegative
• what makes a molecule polar?

  1. different atoms bonded
  2. unsymmetrical
  3. polar
• what makes a molecule nonpolar?

  1. same atoms
  2. symmetrical
  3. dipole-dipole forces cancel out
  4. nonpolar