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AQA A LEVEL CHEMISTRY PAPER 1 Question and Answers TOF steps 1) ionisation 2) acceleration 3) ion drift 4) detection 5) analysis Electron impact Sample vaporised and electron gun fires high energy electrons at it which knock off 1 electron from each particle, making them 1+ ions NB- can knock off more than one e or break molecular ion electrospray ionization Sample dissolved in volatile solvent then injected through needle to give fine mist which is attached to positive en...

Practical’s Chemistry AQA A-level Questions and Answers Required Practical 1 - titration and making a standard solution Making a standard solution 1. weigh the required mass of solid using a sample bottle on a 2 dp balance. 2. transfer the solid into a beaker using distilled water to wash it out- preventing any solid remaining in the sample bottle. 3. reweigh the sample bottle and work out the difference. 4. Add 100cm3 of distilled water to the beaker to dissolve the solid (small...

OCR A Level Chemistry Transition metal colours [Cu(H2O)6]2+ Pale blue Solution [Fe(H2O)6]2+ Pale green solution [Fe(H2O)6]3+ Yellow Solution [Mn(H2O)6]2+ Pale Pink Solution [Cr(H2O)6]3+ Pale Purple Solution Cu(OH)2 Pale Blue PPT Fe(OH)2 Green PPT which darkens on standing Fe(OH)3 Orange Brown PPT Mn(OH)2 Light brown PPT which darkens on standing Cr(OH)3 Grey-green PPT [Cr(OH)6]3- Dark green solution Cr2O7 2-...

AQA A-Level Chemistry - Amount of Substance Questions and Answers Relative Atomic Mass The average mass of an atom of an element, compared to that of the mass of 1/12th of the average mass of an atom of carbon-12 Relative Molecular Mass The average mass of one molecule compared to 1/12th of the mass of one atom of carbon-12 Avogadro Constant The number of particles in one mole of an atom: 6.022 x 10^23 Solvent A liquid that can have a substance dissolved into it ...

AQA A Level Chemistry- Inorganic chemistry Questions and Answers Periodic table Table that provides chemists with a structural organisation of the known chemical elements that can be used to deduce physical and chemical properties Atomic radius across Period 3 Decreases First ionisation energy across Period 3 Increases Exceptions: Drops at Al and S Melting points across Period 3 Increases from Na to Si Decreases from Si to Ar Small rise at S Explain why the me...

AQA A level - Organic Chemistry Questions and Answers Organic compounds Compounds that contain a chain of carbon atoms Number of electrons in carbons outer shell 4 so can form 4 covalent bonds Carbon-Carbon bonds are... non-polar and relatively strong Empirical formula the simplest whole number ratio of atoms of each element in a compound molecular formula a formula that tells us the actual number of atoms of each different element in a compound structura...

A-Level Chemistry Paper 1 Definitions Questions and Answers Orbital A region around the nucleus that can hold up to two electrons with opposite spins First Ionisation Energy The energy required to remove 1 mole of electrons from 1 mole of gaseous atoms Ionic bonding The electrostatic attraction between positive and negative ions Covalent bonding The strong electrostatic force of attraction between a shared pair of electrons and the nuclei of the bonded atoms Dati...

AQA A Level Chemistry Required Practical 10 Questions and Answers Why is the minimum volume of solvent used ? To make a saturated solution To increase the yield of the compound (enable crystallisation on cooling) Why do you hot filter the solution ? Remove insoluble impurities Prevent crystals reforming Why do you need to cool the beaker solution in ice ? Crystals reform (ice increases yield) Soluble impurities in solution Why use suction filtration ? The water pum...

OCR Chemistry A-Level - Modules 1-4 Questions and Answers what is water of crystallisation? water molecules that make up part of the crystal structure of a solid define relative isotopic mass the ass of an atom of an isotope of an element relative to one twelfth the mass of an atom of C-12 why is relative atomic mass written as a decimal? it is a weighted average mass define molecular formula the actual number of atoms of each element in a compound define what...

AQA A Level Chemistry - Shapes of Molecules Questions and Answers V-Shaped 118 2 bonding pairs, 1 lone pair, 118 Tetrahedral 4 bonding pairs, 0 lone pairs, 109.5 Pyramidal 3 bonding pairs, 1 lone pair, 107 V-Shaped 104.5 2 bonding pairs, 2 lone pairs, 104.5 Trigonal Bipyramid 5 bonding pairs, 0 lone pairs, 120 + 90