9701_w20_qp_22
A paper of Chemistry, 9701
Questions:
4
Year:
2020
Paper:
2
Variant:
2
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1
Atoms contain the subatomic particles electrons, protons and neutrons. Protons and electrons were discovered by observations of their behaviours in electric fields. The diagram shows the behaviour of separate beams of electrons and protons in an electric field. source charge on plate charge on plate electrons protons Complete the diagram with the relative charge of each of the electrically charged plates.  On the diagram, draw a line to show how a separate beam of neutrons from the same source behaves in the same electric field. Electrons in atoms up to 36Kr are distributed in s, p and d orbitals. State the number of occupied orbitals in an isolated atom of 36Kr. type of orbital s p d number of orbitals  Complete the diagram to show the number and relative energies of the electrons in an isolated atom of 14Si. 4s 3p 3s 2p 2s 1s  The diagram shows a type of orbital. State the total number of electrons that exist in all orbitals of this type in an atom of 9F. The first ionisation energies of elements in the first row of the d block (21Sc to 29Cu) are very similar. For all these elements, it is a 4s electron that is lost during the first ionisation. Suggest why the first ionisation energies of these elements are very similar. Hydron is a general term used to represent the ions 1H+ , 2H+ and 3H+ . State, in terms of subatomic particles in the nucleus, what is the same about each of these ions and what is different. same different  
1. Atomic structure  →  1.3. Electrons, energy levels and atomic orbitals
1. Atomic structure  →  1.1. Particles in the atom and atomic radius
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The Period3 elements, Na to S, all react with oxygen to form oxides. State the trend in acid/base behaviour of the oxides of the Period3 elements, from Na to S. State and explain the trend, from Na to S, in the maximum oxidation number of the Period3 elements in their oxides. Sodiumoxide and phosphorus(oxide both react with water. Name the product of each reaction. reaction product sodium oxide with water phosphorus(oxide with water  Explain why phosphorus(oxide has a low melting point of approximately 300 °C but magnesiumoxide has a high melting point of approximately 2850 °C. Aluminiumoxide, Al 2O3, reacts separately with both acids and alkalis. Write an equation for the reaction of aluminiumoxide with excess aqueous hydrochloricacid. Write an equation for the reaction of aluminiumoxide with excess aqueous sodiumhydroxide. Describe the lattice structure of silicon(oxide. Your answer should include reference to the arrangement of the silicon and oxygen atoms and the bonds between them. Sodiumoxide and silicon(oxide react to form sodiumsilicate(, Na2SiO3. Sodiumoxide is obtained from the thermal decomposition of sodiumcarbonate. Write equations for the following reactions: sodiumoxide with silicon(oxide the thermal decomposition of sodiumcarbonate, forming sodiumoxide and carbondioxide. 
9. The Periodic Table: chemical periodicity  →  9.2. Periodicity of chemical properties of the elements in Period 3
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PCl 5, PCl 3 and NCl 3 are halides of Group15 elements. PCl 5 can be formed from the reaction of phosphorus with chlorine. PCl 5 has a melting point of 161 °C. Write an equation for the formation of PCl 5 from the reaction of phosphorus and chlorine. State the type of structure and bonding shown by liquid PCl 5. A small amount of PCl 5 is added to excess water. The PCl 5 reacts vigorously to form a colourless solution. Give one other observation you would make when PCl 5 reacts with excess water. Write the equation for the reaction of PCl 5 with excess water. Estimate the pH of the resulting solution. PCl 3 is used to convert alcohols to chloroalkanes, such as compound T. Cl Cl T A possible synthesis of T is shown. Cl Cl HO OH OH HO O reaction 1 using PCl 3 Identify a reagent that could be used in reaction1. T exhibits optical isomerism. Explain what is meant by the term optical isomer and circle any atomin T that give rise to optical isomerism. Cl Cl T  T is a minor product in the reaction of compoundS with excess HCl. S Draw the structure of the major product of the reaction of S with excess HCl.  NCl 3 is a yellow liquid that can be used to bleach flour. Predict the shape of the NCl 3 molecule and the Cl –N–Cl bond angle. shape bond angle  NCl 3 reacts with water to form HOCl, a weak Brønsted-Lowry acid. Explain fully what is meant by the term weak Brønsted-Lowry acid. NCl 3decomposes according to the equation shown. 2NCl 3→ N2+ 3Cl 2A sealed container of volume 250 cm3 contains an unreactive gas at a pressure of 1.00×105Pa. 0.241 g of NCl 3was injected into the sealed container. The sealed container was heated to make the NCl 3decompose fully and then cooled to 20 °C. Calculate the final total pressure inside the sealed container at 20 °C after the NCl 3has fully decomposed.  final total pressure = Pa  
11. Group 17  →  11.4. The reactions of chlorine
9. The Periodic Table: chemical periodicity  →  9.2. Periodicity of chemical properties of the elements in Period 3
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Some reactions of compoundG are shown. OH H O G OH HO O reaction 3 reaction 4 H2SO4, heat under reflux HOOC(CH2)2COOH Tollens’ reagent reaction 2 reaction 1 Na H O O State the type of reaction that occurs in reaction1. Suggest the reagentand conditions required for reaction1. Draw the structure of the organic product, H, from reaction2.  State what you would observe in reaction3. Give the type of reaction shown by reaction4. G and J are structural isomers of each other. OH H O G H O OH J Name the type of structural isomerism shown by G and J. Suggest one chemical test that can distinguish G from J. Give the result of the test with each compound. test result with G result with J  In the reaction schemes below, G and J are converted into organic compoundK. G K NaBH4 HO(CH2)3CH2OH Al 2O3 heat Al 2O3 heat J NaBH4 HO(CH2)2CH(OH)CH3 State the role of NaBH4 in the reactions with G and J. Identify the organic product K. P and Q have the same molecular formula as G. HO O P OH O Q Complete the table with the expected observations for the reactions of P and Q with the named reagents. reagent result with P result with Q Br22,4-dinitrophenylhydrazine aqueous sodium carbonate  The structure of compoundL is shown. R represents a hydrocarbon chain. O L O R A student was asked to deduce the full structure of L. The student analysed L using infrared spectroscopy. The following spectrum was obtained. transmittance % wavenumber / cm–1 Z X Y Identify the bonds responsible for the absorptions marked X and Z. X Z  AbsorptionY shows that L has a C=C bond present in the R group. The student decided to treat L with hot concentrated acidified potassiummanganate(. The products of the reaction are shown. O L O R O O O hot concentrated acidified KMnO4 OH + M CH3(CH2)4COOH Name M. Use the information in to deduce the molecular formula of L.  molecular formula of L = 
14. Hydrocarbons  →  14.2. Alkenes
17. Carbonyl compounds  →  17.1. Aldehydes and ketones
13. An introduction to AS Level organic chemistry  →  13.1. Formulas, functional groups and the naming of organic compounds
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