AQA Chemistry As Level Paper 1 Questions & Correct Answers/ Graded A

State the electron rules : Lowest energy filled first (3d>4s) Line up parallel Single until forced to pair Electronegativity : The ability of an atom to attract electrons within a covalent bond RAM (relative atomic mass) : Average mass of one atom compared to 1/12th the mass of a c-12 atom - Ionisation energy : The energy required to remove one mole of electrons from each of one mole of gaseous atoms to form one mole of positive gaseous ions 2 (Endothermic) Trends of Ionisation Energy : Across a period, i.e increases as there is no increase in shielding but an increase in atomic number Decrease down a group due to increased shielding reducing the electrostatic force of attraction from the nucleus Drop at 2,3 : Al - Between groups 2,3... first electron in p orbital - increase in shielding - reduce forces of attraction - less energy required to remove Drop at 4,5 : P - between groups 4-5 there is a drop - First electron pairing - increased repulsion - less energy is required to remove an eleccte 3 Isotopes : Atoms with the same atomic number but a different mass number - do not react differently as same electron configuration Factors Affecting I.E : -Atomic Radius -Shielding -Effective Nuclear Charg