Chemistry As Level OCR Revision

109.5 - What is the bond angle of a central atom with 4 electron pairs and no lone pairs, in degrees? 2.5 - How much degrees does it go down by each time you add a lone pair to a central atom with 4 electron pairs? 2+ ions. - What ions do Group 2 elements form? 2NaOH(aq) + Cl2(aq)= NaClO(aq) + NaCl(aq) + H20(l) - What is the equation to produce bleach? Including state symbols? A difference in charge between two atoms caused by a shift in electron density in the bond. - What is a dipole? A reaction where an element is simultaneously oxidised and reduced. - What is the definition of a disproportionation reaction? A repeating pattern of properties shown across different periods. - What is periodicity? A shared pair of electrons which has been provided by one of the bonding atoms . - What is the definition of a dative covalent bond (coordinate bond)? Acids. - What are proton donors? actual mass/predicted mass x 100 - How do you calculate percentage yield? Add silver nitrate. - Which test can be done to check for halide ions? Ag+(aq) + Cl-(aq)= AgCl(s) - What is the ionic equation for the silver nitrate test with Chlorine? Including state symbols? Atomic Radius, Nuclear Charge, Electron Shielding - What are the 3 things that affect first ionisation energy? Because of the weak forces between layers. - Why does Graphite feel slippery? Because the covalent bonds are too strong to break. - Why is Graphite insoluble? Because their metallic bonds are too strong to break. - Why are metals insoluble? Because water molecules are polar, so they pull ions away from the lattice and cause it to dissolve. - Why do ionic compounds dissolve in water?