Mr Barnes Teaches Chemistry Codes - How To:

I have given each outcome for the GCSE a code, which you can find below.

Look through the codes (CH1, etc...) and if you want to find out some information about it, add the number to the code finder at the top of the page. This will take you to a revision section with a revision video and revision material.

I am working on practice questions and model answers - these will follow. 

I hope you find it useful! 

Mr Barnes

CH1 - Recall the formulae of elements, simple compounds, and ions

CH2 - Pick information from the text to write word equations

CH3 - Write word equations for the reactions of metals with oxygen

CH4 - Write word equations for the reactions of metals with water

CH5 - Write word equations for the displacement reactions

CH6 - Write word equations for complete combustion

CH7 - Write word equations for the reactionsbetween Acids and Bases

CH8 - Write word equations forreduction reactions

CH9 - Write simple balanced equations when given the formula of the reactants and products

CH10 - Use state symbols to strengthen Chemical Equations

CH11 - Write balanced chemical equations when given the names of the reactants and products

CH12 - Write balanced chemical equations for the reactions of metals with oxygen

CH13 - Write balanced chemical equations for the reactions of metals with water

CH14 - Write balanced chemical equations for the displacement reactions

CH15 - Write balanced chemical equations for complete combustion

CH16 - Write balanced chemical equations for the reactions between Acids and Bases

CH17 - Write balanced chemical equations for reduction reactions

CH18 - Write balanced ionic equations

CH19 - Write balanced ionic equations for neutralisation reactions

CH20 - Write balanced ionic equations for precipitation reactions

CH21 - Write balanced ionic equations for displacement reactions

CH22 - Evaluate the risks in a practical procedure and suggest suitable precautions

CH23 - Draw simple graphs

CH24 - Interpret data from tables

CH25 - Calculate percentages

CH26 - Calculate Means

CH271 - Investigate variables in an experiment

CH27 - Describe how ideas of the atom have changed

CH28 - Describe the structure of the atom

CH29 - Identify the charge and mass of the sub-atomic particles

CH30 - Explain why atoms are neutral

CH31 - Compare the size of the nucleus to the atom

CH32 - Identify where most of the mass of the atom is

CH33 - Recall the meaning of the term mass number

CH34 - Describe why the atomic number is unique

CH35 - Calculate the number of protons, neutrons and electrons in an atom

CH36 - Draw and write the electronic configuration for elements 1-20

CH37 - Relate the electronic configuration to the position on the periodic table

CH38 - Describe what an isotope is

CH39 - Explain why some mass numbers are not whole

CH40 - Calculate the relative atomic mass of an isotope

CH41 - Estimate the abundance of different isotopes

CH42 - Describe how Mendeleev arranged the Periodic Table

CH43 - Describe how Mendeleev predicted the properties of unknown elements

CH44 - Explain why Mendeleev was wrong when he ordered elements by atomic mass

CH45 - Relate the atomic number to the position in the periodic table

CH46 - Describe how the periodic table is structured

CH47 - Explain the position of metals and non-metals on the Periodic Table

CH48 - Explain how ionic bonds form

CH49 - Describe what an ion is

CH50 - Calculate the number of protons, neutrons and electrons in an ion

CH51 - Explain the formation of ions in groups 1, 2, 6 and 7

CH52 - Draw dot and cross diagrams to show ionic bonding

CH53 - Explain the use of the endings –ide & –ate in compounds

CH54 - Work out the formula of ionic compounds when given the charges of the ions

CH55 - Explain the lattice structure of ionic compounds

CH56 - Explain why ionic compounds have high melting points

CH57 - Explain why ionic compounds only conduct when molten

CH58 - Explain what a covalent bond is

CH59 - Describe what a molecule is

CH60 - Identify the size of covalent molecules

CH61 - Use dot and cross diagrams to explain covalent bonding

CH62 - Explain why simple covalent compounds have low melting points

CH63 - Explain why simple covalent compounds do not conduct electricity

CH64 - Use Diamond and Graphite to explain what giant covalent substances are

CH65 - Describe the structures of graphite and diamond

CH66 - Explain the uses of diamond and graphite

CH67 - Explain the properties of fullerenes and graphene

CH68 - Explain why metals have high melting points

CH69 - Explain why metals can conduct electricity

CH70 - Explain why metals are malleable

CH71 - Describe the properties of metals and non-metals

CH72 - Describe what polymers are

CH73 - Describe the limitations of models

CH74 - Recall the properties of each type of bonding

CH75 - Identify the type of bonding occurring from a table of properties

CH76 - Explain how to investigate the type of bonding occurring

CH77 - Explain how and why elements and compounds can be classified

CH78 - Calculate relative formula mass

CH79 - Calculate the empirical formulae of a compound from reacting masses

CH80 - Work out the simplest ratio and molecular formula of a compound

CH81 - Describe an experiment to determine the empirical formula of magnesium oxide

CH82 - Explain the law of conservation of mass

CH83 - Calculate masses of reactants and products from balanced equations

CH84 - Calculate the concentration in g dm⁻³

CH85 - Describe the moles of a substance, including Avogadro's constant

CH86 - Calculate the number of moles, mass and particles of a substance

CH87 - Describe what the limiting reactant is in a chemical reaction

CH88 - Deduce the stoichiometry of a reaction from the masses of the reactants and products

CH89 - Describe the properties of solids, liquids and Gases

CH90 - Explain what is happening during state changes

CH91 - Explain state changes using Melting Point graphs

CH92 - Predict the state of different substances

CH93 - Explain the meaning of 'Pure' in Chemistry

CH94 - Draw Melting Point graphs for pure and impure solids

CH95 - Explain how to separate an insoluble solid from a mixture

CH96 - Explain how to separate a soluble solid from a solution

CH97 - Explain how to separate a soluble and insoluble solid from a mixture

CH98 - Describe how to set up a paper chromatogram

CH99 - Describe the different phases of paper chromatography

CH100 - Interpret a chromatogram

CH101 - Calculate the Retention Factor for a chromatogram

CH102 - Explain how simple distillation can be used to separate mixtures of liquids

CH103 - Explain how fractional distillation can be used to separate multiple liquids

CH104 - Explain how to separate two substances

CH105 - Core Practical: Investigate the composition of inks

CH106 - Describe how to make saltwater potable (safe to drink)

CH107 - Explain the stages necessary to make lake water potable (safe to drink)

CH108 - Explain the importance of chemical analysis

CH109 - Describe acids and alkalis in terms of ions

CH110 - Identify the pH of acids, alkalis and neutral substances

CH111 - Identify the effect of acids and alkalis on indicators

CH112 - Explain the terms dilute and concentrated

CH113 - Explain the terms weak and strong acids

CH114 - Describe what a base is

CH115 - Describe what an alkali is

CH116 - Explain the general reactions of aqueous solutions of acids with metals

CH117 - Explain the general reactions of aqueous solutions of acids with metal oxides/hydroxides

CH118 - Explain the general reactions of aqueous solutions of acids with metal carbonates

CH119 - Describe the chemical test for hydrogen

CH120 - Describe the chemical test for carbon dioxide

CH121 - Explain what is seen when an acid is added to a base

CH122 - Explain acid-alkali reactions in terms of ions

CH123 - Link the concentration of ions to the pH of acids and alkalis

CH124 - Work out the change in pH when the concentration increases by a factor of 10

CH125 - Explain how to prepare a soluble salt from an acid and an insoluble reactant

CH126 - Core Practical: Investigate the preparation copper sulfate crystals 

CH127 - Core Practical: Investigate the change in pH

CH128 - Explain how to prepare a soluble salt from an acid and a soluble reactant

CH129 - Describe how to carry out an acid-alkali titration to prepare a pure, dry salt

CH130 - Recall the main rules of solubility

CH131 - Predict whether a precipitate will form in a displacement reaction

CH132 - Describe the method used to prepare a pure, dry sample of an insoluble salt

CH133 - Describe what electrolytes are

CH134 - Describe the process of electrolysis

CH135 - Explain the movement of ions during electrolysis

CH136 - Explain how electrolysis can be used to purify copper

CH137 - Investigate the electrolysis of copper sulfate (CORE PRACTICAL)

CH138 - Explain the formation of the products in electrolysis

CH139 - Write half equations for electrolysis

CH140 - Explain oxidation and reduction in terms of electrons

CH141 - Describe where oxidation and reduction are occurring during electrolysis

CH142 - Deduce the reactivity of metals, by their reactions with water, acids, and salt solutions

CH143 - Explain displacement reactions as redox reactions, in terms of gain or loss of electrons

CH144 - Explain the reactivity series of metals in terms of the reactivity with water and dilute acids

CH145 - Explain the link between reactivity and rate of oxidation

CH146 - Recall how metals are found in the Earth's crust

CH147 - Explain oxidation as the gain of oxygen and reduction as the loss of oxygen

CH148 - Recall that the extraction of metals involves reduction of ores

CH149 - Explain how to extract a metal from its ore 

CH150 - Evaluate alternative biological methods of metal extraction (bacterial and phytoextraction)

CH151 - Evaluate the advantages of recycling metals

CH152 - Describe what a lifetime assessment for a product involves

CH153 - Evaluate data from a life cycle assessment of a product

CH154 - Recall that chemical reactions are reversible

CH155 - Explain what is meant by dynamic equilibrium

CH156 - Describe the formation of ammonia

CH157 - Recall the conditions for the Haber process

CH158 - Predict the position of a dynamic equilibrium 

CH159 - Recall the typical properties of the transition metals.

CH160 - Describe how corrosion forms

CH161 - Explain how rusting of iron can be prevented

CH162 - Explain the uses of electroplating

CH163 - Explain how alloying makes metals stronger

CH164 - Explain how the uses of metals are related to their properties

CH165 - Calculate the concentration of solutions in moldm⁻³ and convert into g dm⁻³ 

CH166 - Core Practical: Carry out an accurate acid-alkali titration

CH167 - Carry out simple calculations using the results of titrations

CH168 - Calculate the percentage yield

CH169 - Explain why the actual yield is usually less than 100%

CH170 - Recall and calculate the atom economy

CH171 - Explain how to choose an appropriate reaction pathway

CH172 - Describe and calculate molar volumes

CH173 - Calculate volumes of gases using Avogadro’s law.

CH174 - Describe the factors that affect the yield of Ammonia in the Haber Process

CH175 - Describe the composition and uses of fertilisers

CH176 - Describe the formation of ammonium nitrate fertiliser

CH177 - Describe the formation of ammonium sulfate fertiliser

CH178 - Describe what a chemical cell is

CH179 - Describe what happens in a hydrogen-oxygen fuel cell

CH180 - Evaluate the strengths and weaknesses of fuel cells

CH181 - Identify the different groups in the Periodic Table

CH182 - Recall the physical properties of the alkali metals

CH183 - Describe the reactions of lithium, sodium and potassium with water

CH184 - Describe the pattern in reactivity of the alkali metals

CH185 - Explain the reactivity of the alkali metals

CH186 - Explain why the noble gases are chemically inert

CH187 - Explain the uses of the noble gases

CH188 - Describe the pattern in the physical properties of the noble gases

CH189 - Recall the colours and states of Cl₂, Br₂ & I₂

CH190 - Describe the properties of the halogens

CH191 - Describe the chemical test for chlorine

CH192 - Describe the formation of metal halides

CH193 - Describe what happens when hydrogen halides are dissolved in water

CH194 - Describe how to use displacement reactions to prove the reactivity of the halogens

CH195 - Explain displacement reactions of the halogens in terms of oxidation and reductions

CH196 - Explain the reactivity of the halogens in terms of electronic configurations

CH197 - Investigate the effects of changing the conditions on rates of reaction (Core Practical)

CH198 - Explain what is necessary for a chemical reaction to occur

CH199 - Explain how to increase the rate of reaction in terms of collision theory.

CH200 - Interpret graphs of mass, volume or concentration of reactant or product against time

CH201 - Give examples of energy changes in reactions

CH202 - Describe endothermic and exothermic changes in terms of heat energy

CH203 - Draw and label reaction profiles for endothermic and exothermic reactions

CH204 - Explain what happens, in terms of energy, when bonds break and bonds form

CH205 - Explain how a chemical reaction is either exothermic or endothermic overall

CH206 - Calculate the energy change in a reaction given the energies of bonds (in kJ mol⁻¹)

CH207 - Describe what a catalyst is

CH208 - Explain the term activation energy

CH209 - Describe what an enzyme is

CH210 - Explain the effect of catalysts on activation energy

CH211 - Describe what a hydrocarbon is

CH212 - Describe what crude oil is made up of

CH213 - Explain what a homologous series is

CH214 - Describe the term "non-renewable"

CH215 - Describe and explain fractional distillation

CH216 - Recall the names and uses of the fractions of crude oil

CH217 - Explain how the properties of the fractions of crude oil differ from each other

CH218 - Explain the process of cracking

CH219 - Explain why cracking is necessary

CH220 - Describe complete combustion using word and symbol equations

CH221 - Describe what incomplete combustion is using word and symbol equations

CH222 - Explain how carbon monoxide behaves as a toxic gas

CH223 - Describe the problems caused by incomplete combustion

CH224 - Evaluate the advantages and disadvantages of using hydrogen as a fuel in cars

CH225 - Explain how acid rain forms

CH226 - Explain the effects of acid rain

CH227 - Explain how oxides of nitrogen form, and their effects

CH228 - Describe the formation of the Earth's early atmosphere

CH229 - Explain how the Earth's oceans formed

CH230 - Explain how carbon dioxide levels have decreased since the oceans formed

CH231 - Explain the effects of primitive plants on the atmosphere

CH232 - Describe the chemical test for oxygen

CH233 - Explain the greenhouse effect

CH234 - Evaluate the evidence for human activity causing climate change

CH235 - Describe the possible effects of climate change

CH236 - Explain how the effects of climate change can be mitigated

CH237 - Explain why the test for any ion must be unique

CH238 - Describe how to carry out flame tests

CH239 - Describe tests to identify the ions using sodium hydroxide solution

CH240 - Describe the test for ammonia

CH241 - Describe tests to identify different anions

CH242 - Core Practical: Identify the ions in unknown salts

CH243 - Describe the advantages of instrumental methods

CH244 - Evaluate data from a flame photometer

CH245 - Recall and draw the structure of different alkanes

CH246 - Recall and draw the structure of different alkenes

CH247 - Describe the test for alkanes and alkenes

CH248 - Describe the complete combustion of alkanes and alkenes

CH249 - Recall and draw the structure of different alcohols

CH250 - Describe the dehydration of alcohols

CH251 - Core Practical: Investigate the temperature rise per gram by the combustion of alcohols

CH252 - Describe the production of ethanol by fermentation

CH253 - Explain how to obtain a concentrated solution of ethanol by fractional distillation

CH254 - Describe the addition polymerisation of ethene to form polyethene

CH255 - Describe the addition polymerisation of polypropene, PVC and Teflon

CH256 - Deduce the structure of a monomer from the structure of a polymer and vice versa

CH257 - Explain how the uses of polymers are related to their properties

CH258 - Describe the problems associated with polymers

CH259 - Link knowledge of polymers to DNA, Starch and Proteins

CH260 - Recall and draw the structure of carboxylic acids

CH261 - Describe the properties of carboxylic acids

CH262 - Describe how alcohols can be oxidised to produce carboxylic acids

CH263 - Explain what polyesters are using condensation polymerisation

CH264 - Compare the size of nanoparticles with the sizes of atoms and molecules

CH265 - Calculate the surface area- to-volume ratio for nanoparticles

CH266 - Describe how the properties of nanoparticulate materials are related to their uses

CH267 - Explain the risks associated with nanoparticles

CH268 - Describe the physical properties of glass and clay ceramics

CH269 - Describe the physical properties of composites

CH270 - Compare the physical properties of ceramics, polymers, composites, and metals