Chem
some stuff, redox and stuff
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Chem - Leaderboard
Chem - Details
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107 questions
| 🇬🇧 | 🇬🇧 |
| K | Is K or K+ bigger? |
| The ability of an atom to pull the e- towards it within a bond | Electronegativity |
| Difference in electronegativity over 0.8 | What makes it polar |
| Absorbs wavelengths of light, splitting of the d shell into sub-levels, ligands, and oxidation states can cause colors | What can cause colors |
| Single bond | Weakest bond |
| Single bond bonds | Sigma |
| Double bond bonds | Sigma pi |
| Triple bond bonds | Sigma pi pi |
| Electronegativity _ down a group and _ across a period | Electronegativity decreases down a group and decreases across a period |
| Electron affinity _ down a group and _ across a period | Electro affinity decreases down a group and increases across a period |
| Radius _ down a group and _ across a period | Radius increases down a group and decreases across a period |
| Ionization energy _ down a group | Ionization energy decreases down a group |
| 2 possible structures "sharing" a double bond. Bond energy is going to be about 1.5 bond value | Resonance structure |
| Sulphate | SO4 2- |
| Nitrate | NO3 - |
| Carbonate | CO3 2- |
| Ammonium | NH4 + |
| Strongest to weakest structures | Giant covalent, metals, ionic structures, simple covalent |
| No dipole, all | Dispersion |
| Dipole, + and - | Dipole-dipole |
| Dipole, H to F, O, N | Hydrogen bonding |
| Bond breaking, energy absorbed. | Endothermic |
| Bond making, energy released | Exothermic |
| ΔH | SumE(break) - SumE(formed) |
| WA+WB at equivalence point | Similar pKa - closer to 7 |
| Ka = _ at _ | Ka = [H+] at half equivalence point |
| 3+ ions in solutions... | Are acidic |
| Wb + its salt | Basic buffer |
| H2O -> OH- + H+ | Disassociation of water |
| 1x10^-14 | Kw value |
| Kw (in terms of Ka and Kb) | Ka x Kb |
| PKw (in terms of pKa and pKb) | PKa + pKb |
| -log[H+] | PH |
| Higher pKa = | A weak acid |
| Strong acids have | Weak conj. bases |
| Lewis acid | Lone pair acceptor |
| Lone pair donor | Lewis base |
| Molecule that produces H+ ions in water | Arrhenius acid |
| Molecule that produces OH- ions in water | Arrhenius base |
| -log[OH-] | POH |
| Acid + base -> | Salt + water |
| Acid + carbonate -> | Salt + water + CO2 |
| Acid + metal -> | Salt + H2 |
| Base soluble in water | Alkali |
| The only thing that can change Kw | TEMPERATURE |
| Sulphuric acid | H2SO4 |
| Nitric acid | HNO3 |
| Phosphoric acid | H3PO4 |
| Species which differ by 1 proton | Conjugate acids and bases |
| Acts as acid or base | Amphoteric |
| Can act as a BL base and a BL acid | Amphiprotic |
| Strong vs weak acids | Can look at conductivity |
| Ka/b will be higher | Strong acid/base |
| When pH changes by 1... | Concentration will change by 10x |
| Dry deposition | Smoke/dust |
| Carbon dioxide in acid rain | CO2 + H2O <-> H2CO3 |
| Limestone in acid rain | CaCO3 + H2SO4 -> CaSO4 + H2O + CO2 |
| Pre-combustion prevention | Removing sulpher before combustion of the coal |
| Removing sulpher oxides from the exhaust gases after reacting with base | Post-combustion prevention |
| CuO | Copper (111) oxide |
| Calcium hydroxide | Ca(OH)2 |
| 14 (in terms of ps) | PKa + pKb |
| Sulpher creation for acid rain | S + O2 -> SO2 |
| Sulpher creation for acid rain after SO2 | SO2 + H2O -> H2SO3 |
| Nitric acid equations for acid rain (all) | N2 + O2 -> 2NO* 2NO* + O2 -> 2NO2* 2NO2* + H2O -> HNO3 + HNO2 |
| Relative charges on atoms in covalent compounds | Oxidation state |
| Maximum oxidation state for an element | Group number |
| Oxidise other species (takes e-) | Oxidising agent |
| Reduce other species (gives e-) | Reducing agent |
| C= | N/v |
| Mass | Mol x mr |
| Winkler | Calculate mols, /4, use concentration formula |
| Provides measure of tendency for rxn to happen | Cell potential |
| More reactive displaces the less reactive metal | Displacement |
| More reactive means the metal is... | A stronger reducing agent |
| What's at the anode (electrolysis) | Oxidation, +ve eletrode |
| What's at the cathode (electrolysis) | Reduction, -ve electrode |
| Use redox to generate electricity | Voltaic cells |
| Electrons flow from the... | More reactive metal the less |
| Cell notation | Ox||red |
| More -ve Eø | Stronger reducing agent |
| ...affect the molar volume of an ideal gas. | Pressure and temperature |
| Mr/avo's | Mass of 1 molecule |
| Mass of element in compound/mr of compound x 100 | Percentage composition |