A- Level Chemistry Q&A Mastery Guide

Atomic number Number of protons in an element Mass number Number of protons and neutrons Ion Electrically charged particle formed by the loss/gain of electrons Relative masses of P,N and E 1,1, 1/2000 (respectively) Isotopes Atoms of the same element with different number of neutrons but same ...

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 wei...

What is the relative mass and charge on a proton? Mass 1 charge +1 What is the relative mass and charge on a neutron? Mass 1 Charge 0 What is the relative mass and charge on an electron? Mass 1/2000 Charge -1 What is the mass number? The total number of protons and neutrons in the nucleus of...

Silver nitrate+ nitric acid + iodide ions Yellow precipitate Silver nitrate+ nitric acid + bromide ions Cream precipitate Silver nitrate+ nitric acid + iodide ions Yellow precipitate Substances that decolorise bromine water Alkenes Electrophiles Electron pair acceptors, attracted to electrons e....

Bronsted-Lowry acid Proton donor Bronsted-Lowry base Proton acceptor pH Measure of acidity by measuring concentration of H⁺ ions. Low pH means Acidity High pH means Alkalinity

Topic 1 Atomic Structure Topic 2 Amount of Substance State what is meant by the term molecular formula. the actual no. atoms of each element in a compound Topic 3 Bonding Explain why CF4 has a bond angle of 109.5°. -there are 4 bonding pairs and no lone pairs -repel equally and therefore s...

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 elec...

Proton Mass 1 Proton Charge +1 Neutron Mass 1 Neutron Charge 0 Electron Mass 1/1840 Electron Charge -1

Natures of amino acidspolar, non-polar, electrically-charged Properties of amino acidswhite crystalline solids, high melting point, soluble in H2O Effect of pH on enzyme activityincreases then decreases above the optimum pH Why does the enzyme activity decrease above optimum pH?the active site is...

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 ...

How to test for C=C decolourises bromine water Atomic Number number of protons in the nucleus of an atom of that element. Mass Number the sum of protons and neutrons in a nuclues of an atom Isotopes atoms of the same elementwith the same numberof protons but different nuber of neutrons Relativ...

What are nucleons? Nucleons are protons and neutrons in the nucleus. What is the position of protons? Nucleus What is the relative mass of a proton 1 What is the relative charge of a proton? +1 What is the position of neutrons? Nucleus What is the relative mass of a neutron? 1

What is heterolytic fission? Where one ion gets both electrons from the covalent bond What are produced by heterolytic fission? Ions What is a free radical? An atom or group with an unpaired electron, which is highly reactive as it wishes to pair up this electron What are 3 examples of situat...

What is an alkene? An unsaturated hydrocarbon What is an unsaturated hydrocarbon? A compound containing only carbon and hydrogen atoms and containing at least one carbon carbon double bond What are van der Waals forces? Relatively weak intermolecular forces caused by temporary dipole dipole in...