Pearson Edexcel As Level Chemistry Paper 1 June 2023 Question Paper

Bond enthalpy {Ans: The energy required to break one mole of the bonds in a substance in the gaseous state}Reduction {Ans: The gain of electrons}London forces {Ans: Intermolecular forces that exist between all molecules}Polarising power {Ans: An indication to which a positive ion is able to distort the electron cloud around a neighbouring negative ion}Electrolysis {Ans: The decomposition of a compound by electricity}Electronegativity {Ans: The ability of an atom to attract a bonding pair of electrons in a covalent bond}Standard enthalpy of combustion {Ans: The enthalpy change when one mole of the substance burns completely in oxygen under standard condition}Thermal decomposition {Ans: When a compound is decomposed on heating}Group {Ans: Vertical column of elements in the periodic table}Standard enthalpy of neutralisation {Ans: The enthalpy change when the acid and alkali in the equation neutralise each other under standard conditions to form one mole of water}Isoelectric molecules {Ans: Molecules and ions which have exactly the same number and arrangements of electrons}Lattice {Ans: A regular three-dimensional arrangement of atoms or ions in a crystal}Delocalised electrons {Ans: Bonding electrons which are not fixed in a bond between 2 atoms}Stereoisomerism