Save my exams chemistry igcse

Save my exams chemistry igcse. The mass of the electron is negligible, hence the mass of an atom is contained within the The mole, symbol mol, is the SI unit of amount of substance. Are malleable (can be hammered and made into different shapes) and ductile (can be drawn into wires) Tend to be lustrous (shiny) Have high density and usually have high melting points. Untreated water contains soluble and insoluble impurities. The standard unit of mass in kilograms (kg) but in chemistry grams (g) are most often used. Polymers are large molecules of high relative molecular mass and are made by linking together large numbers of smaller molecules called monomers. Rusting of Iron. Paper 1 - Higher. The oxidation number of the element is decreased. Past paper and exam-style questions organised by topic, with student-friendly answers written by teachers and examiners. Diagram showing the first three alcohols. Tools to help you ace your exams, including: past papers, revision notes, and exam-style questions (organised by topic) FREE Chemistry revision notes on Changing Models of the Atom. 6 g of potassium nitrate will dissolve in 20 g of water. Iron is extracted in a large container called a blast furnace from its ore, hematite. Reversible reactions. Physical Properties. 2 × 56 = 112. These coloured compounds are responsible for the pigments in many paints and the colours of gemstones and rocks. Test for water using cobalt chloride paper which turns pink in the presence of water. O Level Chemistry. The group 1 metals are lithium, sodium, potassium, rubidium, caesium and francium and they are found in the first column of the periodic table. The structure of proteins can be represented using the following diagram whereby the boxes represent the carbon chains. Method: Add lead (II) bromide into a crucible and heat so it will turn molten, allowing ions to be free to move and conduct an electric charge. They differ by one -CH 2 in the molecular formulae from one member to the next. These are fluorine, chlorine, bromine, iodine and astatine. FREE Chemistry revision notes on The Three States of Matter. Example: Identifying Redox Reactions. The symbol for an isotope is the chemical symbol (or word) followed by a dash and then the mass number. CoCl 2 (s) + 6H 2 O (l) CoCl 2 . For conventional reasons metal carbonates, carbon dioxide and carbon monoxide are not included in organic compounds. The components have different solubilities in a given solvent (e. Ethanol (C 2 H 5 OH) is one of the most important alcohols. different coloured inks that have been mixed to make black ink) and different adhesion to the supporting medium - usually paper. Their size is so tiny that we can't really compare their masses in conventional units such as kilograms or grams, so a unit called the relative atomic mass is used. Non-renewable fossil fuels are obtained from crude oil by fractional distillation. Paper 2 - Higher. Since water is being added to the molecule it is also called a hydration reaction. One mole contains 6. Potassium promotes growth and healthy fruit and flowers. Flame Tests. (112 ÷ 160) × 100 = 70%. The more reactive the metal then the more vigorous the reaction will be. Alcohols are a homologous series of compounds that have the general formula CnH2n+1OH. The process is demonstrated and explained below: Diagram showing the carbon extraction of iron. Conduct heat and electricity. Our extensive collection of resources is the perfect tool for students aiming to ace their exams and for teachers seeking reliable resources to support their students' learning journey. Designed by the teachers at SAVE MY EXAMS for the Edexcel IGCSE Double Science: Chemistry syllabus. Ethanol can also be represented by its structural formula CH 3 CH 2 OH. Both processes occur in the same chemical reaction, for example, in the production of ammonia: Stewart has been an enthusiastic GCSE, IGCSE, A Level and IB teacher for more than 30 years in the UK as well as overseas, and has also been an examiner for IB and A Level. Notice the question asks for the separation of the solid, not the liquid from the solution. Make your way through our clear revision notes, Chemistry past papers, typical exam questions, fully-explained model answers and more, tailored to your Chemistry specification. Giant covalent structures contain billions of non-metal atoms, each joined to adjacent atoms by covalent bonds forming a giant The transition elements form coloured compounds and often have more than one oxidation state, such as iron readily forming compounds of both Fe 2+ and Fe 3+. A lot of heat energy is needed to break these bonds. Designed by the teachers at SAVE MY EXAMS for the AQA GCSE Chemistry syllabus. Revision notes on 1. E. The graph below shows a reaction profile for the reaction between methane and oxygen. Method: Dissolve lead (II) nitrate and potassium sulfate in water and mix together using a stirring rod in a beaker. Stewart specialises in Chemistry, but has also taught Physics and Environmental Systems and Societies. Concise resources for the IGCSE Edexcel Chemistry Double Science: course. zinc oxide + carbon → zinc + carbon monoxide. Soluble Salt 2 = potassium sulfate. Properties of Acids. ZnO + C → Zn + CO. Paper 1 - Foundation MS. Those metals placed higher up on the series (above carbon) have to be extracted using electrolysis. There are many strong metallic bonds in giant metallic structures between the positive metal ion and delocalised electrons. When acids react with metals they form a salt and hydrogen gas: The general equation is: metal + acid salt + hydrogen. For example: Answers: Problem 1. Number of molecules of gas on the left = 2. Atoms, Elements & Compounds. Oxidation is a reaction in which oxygen is added to an element or a compound. An increase in pressure will cause equilibrium to shift in the direction that produces the smaller number of molecules of gas. 4 Separation & Purification. 5 Identification of Ions & Gases. 6 Carboxylic acids. 1 Atomic Structure & the Periodic Table. Fossil fuels include: coal, oil, natural gas, oil shales and tar sands. C iodine. Oxygen and water must be present for rusting to occur. Proteins can contain between 60 and 600 of these amino acids in different orders. The equation is: anhydrous cobalt (II) chloride + water hydrated cobalt (II) chloride. Method: Measure 50 cm 3 of sodium thiosulfate solution into a flask. Iron + Water + Oxygen → Hydrated Iron (III) Oxide. Paper 2 - Higher MS. 2 Homologous Series for the CIE IGCSE Chemistry syllabus, written by the Chemistry experts at Save My Exams. How to carry out a titration. 1. Student friendly model answers written by experienced teachers & examiners. There are several factors that can affect the rate of a reaction. Elements are made of tiny particles of matter called atoms. Write the ionic equation for the reaction of aqueous chlorine and aqueous potassium iodide. Turn on the power pack or battery and allow electrolysis to Stewart has been an enthusiastic GCSE, IGCSE, A Level and IB teacher for more than 30 years in the UK as well as overseas, and has also been an examiner for IB and A Level. g. Here you’ll find clear revision notes, Chemistry past papers, typical exam questions, fully-explained model answers, and more. Metal ions produce a colour if heated strongly in a flame. Metals conduct electricity. When two or more atoms are covalently bonded together, we describe them as ‘ molecules ’. Anion is a negatively charged ion which is attracted to the anode. Diagram showing the electrolysis of lead (II) bromide. Nitrogen makes chlorophyll and protein and promotes healthy leaves. Leave in an oven to dry. 8 Synthetic polymers. The use of a catalyst. 3. Course-specific and 100% exam-aligned. 1 decimetre cubed (dm 3) is the same as 1 litre. Extraction of Iron from Hematite. Acids have pH values of below 7, have a sour taste (when edible) and are corrosive. Diagram showing the apparatus needed to investigate the effect of concentration on the rate of reaction. Add two graphite rods as the electrodes and connect this to a power pack or battery. 3 Chromatography. Modern blast furnaces produce approximately 10,000 tonnes of iron per day. Which of these solutions are alkaline? A P only. The opposite occurs for forming bonds as it releases energy back to the surroundings in an exothermic process. Revision notes on 12. . when oxygen reacts with magnesium, oxygen is reduced to oxide ions: O 2 + 4e - → 2O 2-. Each atom is made of subatomic particles called protons, neutrons and electrons. Paper 2 - Higher QP. 1 kilogram = 1000 grams. Changes in these factors directly influence the rate of a reaction. Paper 6 Alternative to Practical MS. The elements in group 7 are known as the halogens. Alkanes: Properties & Bonding. Compound. Pressure of 60 - 70 atm. Fertiliser compounds contain the following water-soluble ions: Ammonium ions, NH 4+ and nitrate ions, NO 3 We're on a mission to take the guesswork out of Chemistry revision. The oxide is tested with damp red litmus paper. So C-14 ( or carbon-14) is the isotope of carbon which contains 6 protons, 6 electrons and 14 - 6 = 8 neutrons. Diagram showing condensation polymerisation to produce a protein. FREE Chemistry revision notes on Kinetic Theory. Worked example. A combination of two or more substances (elements and/or An alloy is a mixture of two or more metals or metal with a non-metal such as carbon. An element E is burned in air. - Double Science. Progress tracking across undefined+ topics & undefined+ questions, sorted by difficulty. : Past Papers. The positive and negative ions are held together by strong electrostatic forces of attraction between opposite charges. Polymerisation reactions usually require high pressures and the Isotopes are different atoms of the same element that contain the same number of protons but a different number of neutrons. Period: These are the horizontal rows that show the number of shells of electrons an atom has and are numbered from 1 - 7. A pure substance made up of two or more elements chemically combined. Method: Use the pipette and pipette filler and place exactly 25 cm 3 sodium hydroxide solution into the conical flask. Revision notes on 2. Revision notes on 10. 3 Solubility Rules for the CIE IGCSE Chemistry syllabus, written by the Chemistry experts at Save My Exams. This process is called addition polymerisation. Diamond and graphite are allotropes of carbon which have giant covalent structures. Energy is needed to break bonds which is absorbed from the reaction surroundings, so bond breaking is an endothermic process. Dehydration of hydrated cobalt (II) chloride: hydrated cobalt (II) chloride ⇌ anhydrous cobalt (II) chloride + water. Volume-liquids. Bond Energy. 1 Identification of Anions for the CIE IGCSE Chemistry syllabus, written by Stewart has been an enthusiastic GCSE, IGCSE, A Level and IB teacher for more than 30 years in the UK as well as overseas, and has also been an examiner for IB and A Level. N, P, K Fertilisers. zinc + copper sulphate → zinc sulphate + copper. Chemical equations for reversible reactions. D sulfur. The diagram shows the pH values of four solutions. Others contain two or more different Oxford AQA IGCSE Chemistry. 1 Solids, Liquids & Gases. copper (II) sulfate (CuSO 4 ), calcium carbonate (CaCO 3 ), carbon dioxide (CO 2) Mixture. Form basic oxides. For example, when jewellery or cutlery is coated with silver. These elements are non-metals that are poisonous. Wash precipitate with distilled water to remove traces of potassium nitrate solution. Here, you'll find an array of revision notes, topic questions, fully explained model answers, past exam papers and more, meticulously Catalytic Cracking. Stuck? View related notes. These structures can also be called giant lattices and have a fixed ratio of atoms in the overall structure. B P and Q only. Water treatment. Paper 5 Practical Test MS. Alex’s passion for creating engaging content that enables students to succeed in exams drove her to pursue a career outside of the classroom at SME. Designed by the teachers at SAVE MY EXAMS for the Edexcel IGCSE Chemistry syllabus. Electrode is a rod of metal or graphite through which an electric current flows into or out of an electrolyte. elements in period 2 have two electron shells, elements in period 3 have three electron shells. Jan 12 Paper 1C (QP) Jan 12 Paper 1C (MS) Model Answers. Ammonia is manufactured in an exothermic reaction called the Haber process which occurs in five stages: Stage 1: H 2 and N 2 are obtained from methane and the air respectively and are pumped into the compressor through pipe. 3 Alkanes. Dip the loop of an unreactive metal wire such as nichrome or platinum in concentrated acid, and then hold it in the blue flame S + O 2 → SO 2. The electrons move very fast around the nucleus in orbital paths called shells. The protons and neutrons are located at the centre of the atom, which is called the nucleus. Revision notes on 11. The raw materials: iron ore (hematite), coke (an impure As a long-standing Head of Science, Stewart brings a wealth of experience to creating Topic Questions and revision materials for Save My Exams. Get started by selecting your qualification level, and dive into everything you'll need to make the Electroplating is done because it makes the metal more resistant to corrosion or damage. Paper 2 - Foundation MS. The alkali metals share similar characteristic chemical properties because they each have one Reduction is a reaction in which an element, ion or compound gains electrons. So scaling, 68 x (20 / 100) = 13. A general formula to calculate the concentration in g/dm 3 is: Concentration can be measured in grams per cubic decimetre. Reduction is a reaction in which oxygen is removed from an element or compound. One mole of a substance contains the same number of the stated particles, atoms, molecules, or ions as one mole of any other substance. The reaction mixture becomes paler as more colourless N 2 O 4 is produced. 1 Exothermic & Endothermic Reactions for the CIE IGCSE Chemistry syllabus, written by the Chemistry experts at Save My Exams. Acids are substances that can neutralise a base, forming a salt and water. (2 × 56) + (3 × 16) = 160. Stage 2: The gases are compressed to about 200 atmospheres inside the compressor. Revision notes for the Cambridge O Level Chemistry syllabus, written by the Chemistry experts at Save My Exams. Answer. Soluble Salt 1 = lead (II) nitrate. The reaction is very important industrially for the production of alcohols and it occurs using the following conditions: Temperature of around 300ºC. 4. Phosphorus promotes healthy roots. Paper 2 Multiple Choice (Core) MS. 1 Kinetic Theory for the CIE IGCSE Chemistry syllabus, written by the Topic Questions. The flame test is thus used to identify metal ions by the colour of the flame they produce. 2 Crude Oil. Caroline has over 12 years of experience teaching GCSE and A-level chemistry and physics. Revision notes on 5. 6H 2 O (s) blue pink. They form alkaline solutions when they react with water. Balances must be tared (set to zero) before use. Chemistry. A pressure of 2 atm (200 kPa) Stewart has been an enthusiastic GCSE, IGCSE, A Level and IB teacher for more than 30 years in the UK as well as overseas, and has also been an examiner for IB and A Level. 1 decimetre cubed (dm 3) = 1000 cm 3. Petrol is used as a fuel in cars, kerosene is used to fuel aircraft and diesel oil is used as a fuel in some cars Experimental Techniques & Chemical Analysis. 4 Alkenes. Draw a cross on a piece of paper and put it underneath the flask. Jan 12 Paper 2C (QP) Jan 12 Paper 2C (MS) Model Answers. At 50 °C, the solubility of potassium nitrate is 68 g per 100 g of water. C Q, R and S only. 3 Reducing the Effects of Environmental Issues for the CIE IGCSE Chemistry syllabus, written by the Chemistry experts at Save My Exams. With Save My Exams, your revision resources are created by experienced educators and examiners who actually mark IGCSE exams, so you’ll know exactly what to revise and how to answer questions for maximum marks. Metals that are placed high on the reactivity series such as potassium and sodium are very dangerous and react explosively with acids. View PDF List. Get started. Leverage the knowledge and expertise of40+ examiners and educators. Water is pumped into sedimentation tanks where the water is allowed to stand for a few hours. Performing a titration. Paper 1 - Higher MS. Surface area of solid reactants. The conditions for this main stage of production are: A temperature of 450 ºC. Topic Questions. Problem 2. Step 3: Divide the total Ar of the element by the Mr of the compound, then multiply by 100. The Haber Process. If it asked for the liquid, B would be the correct answer. Organic Chemistry is the scientific study of the structure, properties, and reactions of organic compounds. Soluble impurities include dissolved calcium, metallic compounds and inorganic pollutants. Organic compounds are those which contain carbon. The overall transfer is from the surroundings to the system. Group: These are the vertical columns Topic Questions. Soluble solids are separated by gently heating the solution until the solvent evaporates and the solid crystallises. Number of molecules of gas on the right = 1. Temperature at which the reaction is carried out. Electrolyte is the ionic compound in a molten or dissolved solution that conducts the electricity. 2. The Extraction Method Depends on the Position of a Metal in the Reactivity Series. Halogens are diatomic, meaning they form molecules made of pairs of atoms sharing The group 1 metals are known as the alkali metals. The table is arranged in vertical columns called groups and in rows called periods. The term saturated means that they only have single carbon-carbon bonds, there are no double bonds. A pencil line is drawn on chromatography paper and spots Properties of metals. Metal atoms lose their outer electrons which the non-metal atoms gain to form positive and negative ions. chromatography. FREE Chemistry revision notes on Elements. Some polymers contain just one type of unit. This can be shown in a half equation, e. Paper 2 - Foundation. 2 Enthalpy Change & Activation Energy for the CIE IGCSE Chemistry syllabus, written by the Chemistry experts at Save My Exams. Examples include poly (ethene) and poly (chloroethene), commonly known as PVC. Insoluble impurities include soil, pieces of plants and other organic matter. Measure 5 cm 3 of dilute hydrochloric acid into a measuring cylinder. Only non-metal elements participate in covalent bonding. Questions and model answers for the Edexcel IGCSE Chemistry syllabus, written by the Chemistry experts at Save My Exams. What is element E? A calcium. Alloys often have properties that can be very different from the metals they contain, for example, they can have more strength, hardness or resistance to corrosion or extreme temperatures. Step 2: Work out the total Ar of the element you have been asked about in the question, in this case, iron. Each repeat unit is connected to the adjacent units via covalent bonds. 1. The main stage in the Contact process is the oxidation of sulfur dioxide to sulfur trioxide using a vanadium (V) oxide, V2O5, catalyst: 2SO 2 + O 2 2SO 3. Paper 1 - Higher QP. In endothermic reactions thermal energy is taken in from the surroundings so the temperature of the surroundings decreases. As in ionic bonding, each atom gains a full outer shell of electrons, giving them a noble gas electronic configuration. 12. Therefore for mass of crystals formed = 118 – 64 Metals have high melting and boiling points. All halogens have similar reactions as they each have seven electrons in their outermost shell. D R and S only. She is passionate about creating high-quality resources to help students achieve their full potential. Add a few drops of a suitable indicator to the solution in the conical flask. Polymers are large molecules built by linking 50 or more smaller molecules called monomers. The correct answer is C. Stewart has been an enthusiastic GCSE, IGCSE, A Level and IB teacher for more than 30 years in the UK as well as overseas, and has also been an examiner for IB and A Level. Mass is measured using a digital balance which normally gives readings to two decimal places. Designed by the teachers at SAVE MY EXAMS for the AQA GCSE Combined Science: Chemistry syllabus. There is an unlimited number of compounds. Just select your qualification level ( (I)GCSE, A Level, IB) and exam board below, and dive into everything you’ll need to study smarter, not harder. 5 Alcohols. Fertilisers contain nitrogen, potassium and phosphorus. They are colourless compounds which have a gradual change in their physical properties as the number of carbon atoms in 4. Meet all our experts. Metals lower down on the series can be extracted by heating with carbon. 8. Both substances contain only carbon atoms but due to the differences in bonding arrangements they are physically completely different. Each monomer is a repeat unit and is connected to the adjacent units via covalent bonds. Rusting is a redox process and it occurs faster in salty water since the presence of sodium chloride speeds up the reaction. Answer: Step 1: Calculate the relative formula mass of the compound. The position of the metal on the reactivity series influences the method of extraction. These are the monomers which polymerise to form the protein. Paper 3 Theory (Core) Paper 3 Theory (Core) MS. 1 Experimental Design. Paper 6 Alternative to Practical. Hydrated and anhydrous salts. Using copper (II) sulfate: Introduction. Alkenes are unsaturated hydrocarbons with carbon-carbon double bonds (C=C) Their general formula is CnH2n. Revision notes on 7. N 2 + 3H 2 ⇌ 2NH 3. Three common macromolecules you should know about are diamond, graphite and C 60 fullerene. atoms, ions, molecules); this number is known as the Avogadro Constant. As a long-standing Head of Science, Stewart brings a wealth of experience to creating Topic Questions and revision materials for Save My Exams. 2 Acid-Base Titrations. When acids are added to water, they form positively charged hydrogen ions (H +) The presence of H + ions is what makes a solution acidic. Designed by the teachers at SAVE MY EXAMS for the Edexcel GCSE Chemistry syllabus. Ionic Bonding Definition. Past paper and exam-style questions, organised by topic. Polymers: The Basics. 4. States of Matter. 02 x 1023 particles (e. Example: Identifying the loss and gain of oxygen in an equation. Anode is the positive electrode of an electrolysis cell. B carbon. Diagram showing the dehydration of hydrated cobalt (II) chloride. Covalent compounds are formed when pairs of electrons are shared between atoms. Designed by the teachers at SAVE MY EXAMS for the CIE IGCSE Chemistry 0620 / 0971 syllabus. A white solid oxide is formed. Answer: Step 1: Write out the full balanced equation: 2KI (aq) + Cl 2 (aq) → 2KCl (aq) + I 2 (aq) Step 2: Identify the ionic substances and write down the ions separately. This energy is transferred to the chemical energy store of the chemical system and so the energy of the system increases - this means the energy change is positive. There are free electrons available to move through the structure and carry charge. Filter to remove precipitate from mixture. Place the conical flask on a white tile so the tip of the burette is inside the flask. Form positive ions through electron loss. Example. Alkanes are a group of saturated hydrocarbons. Solubility of lead (II) nitrate at 90 o C is 118 g / 100 g water, and 64 g / 100 g water at 40 °C. So equilibrium shifts to the right. 1 Tests for Gases for the Edexcel IGCSE Chemistry syllabus, written by the Chromatography is used to separate substances and provide information to help identify them. Paper 5 Practical Test. 3 Order of Reactivity for the Edexcel IGCSE Chemistry syllabus, written by Giant covalent structures on the other hand have a huge number of non-metal atoms bonded to other non-metal atoms via strong covalent bonds. It also improves the appearance of the metal. Compounds cannot be separated into their elements by physical means. You may be given data in a question which needs to be converted from cm 3 to dm 3 or the other way around. The presence of the double bond, C=C, means they can make more bonds with other atoms by opening up the C=C bond and allowing incoming atoms to form another single bond with each carbon atom of the functional group The combustion of fossil fuels is the major source of atmospheric pollution. What does the label X represent? Choose your answer. The oxygen used in this stage is obtained from air. Example: Hydrochloric Acid. This test is usually done using cobalt chloride paper. 7 Esters. 2. Transition elements, as elements or in compounds, are often used as Alkenes also undergo addition reactions with steam in which an alcohol is formed. Rusting is a chemical reaction between iron, water and oxygen to form hydrated iron (III)oxide. Ions from different metals produce different colours. These enhanced properties can make alloys more useful than pure metals. The general formula of the alkanes is CnH2n+2. These are: Concentration of the reactants in solution or the pressure of reacting gases. The Structure of the Atom. Did this page help you? Questions and model answers on 5. The paper turns blue. Ionic compounds are formed when metal atoms react with non-metal atoms. Revision notes for the Edexcel IGCSE Chemistry syllabus, written by the Chemistry experts at Save My Exams. Each atom is made of subatomic particles called protons, neutrons, and electrons. ol nk oa xy qy vv ov xd sb sr