0620_s21_qp_31
A paper of Chemistry, 0620
Questions:
8
Year:
2021
Paper:
3
Variant:
1
Login to start this paper & get access to powerful tools
1
The electronic structures of five atoms, A, B, C, D and E, are shown. A B C D E Answer the following questions about these electronic structures. Each electronic structure may be used once, more than once or not at all. State which electronic structure, A, B, C, D or E, represents: an atom in GroupII of the PeriodicTable an atom with a proton number of 13 an atom that forms a stable ion with a single negative charge an atom of a non-metal that forms a giant covalent structure an atom of a metal used in food containers. Complete the table to show the number of electrons, neutrons and protons in the vanadium atom and calcium ion shown. number of electrons number of neutrons number of protons 51V 48Ca2+  
2. Atoms, elements and compounds  →  2.2. Atomic structure and the Periodic Table
Open
2
The table shows the masses of some of the ions in 1000 cm3 of fruit juice. name of ion formula of ion mass of ion in 1000 cm3 of fruit juice / mg NH4 + calcium Ca2+ chloride Cl – lithium Li+ magnesium Mg2+ nitrate NO3 – phosphate PO4 3– potassium K+ sodium Na+ SO4 2– Answer these questions using only the information in the table. State which negative ion has the highest mass in 1000 cm3 of fruit juice. Give the formulae of the ions in ammoniumsulfate. and Calculate the mass of sodium ions in 200 cm3 of fruit juice.  mass = mg Describe a test for lithium ions. test observations  Ions of the element potassium, K, are present in most fertilisers. State the names of two other elements that are in most fertilisers.  Orange juice is acidic. Draw a circle around the pH of orange juice. pH 4 pH 7 pH 10 pH 13 Some soils are acidic. Give the names of two compounds that are used to make soils less acidic.  Hydrogen chloride is an acidic gas produced when concentrated hydrochloricacid evaporates. Describe the arrangement and separation of the molecules in hydrogenchloride gas. arrangement separation  A long glass tube is set up as shown. long glass tube cotton wool soaked in concentrated hydrochloric acid damp blue litmus paper At first, the blue litmus paper does not turn red. After a short time, the litmus paper turns red. Explain these observations using the kinetic particle model. 
7. Acids, bases and salts  →  7.1. The characteristic properties of acids and bases
12. Experimental techniques and chemical analysis  →  12.5. Identification of ions and gases
Open
3
The table shows some properties of four GroupI elements. element melting point / °C boiling point / °C atomic radius / nm sodium 0.191 potassium rubidium 0.250 caesium 0.272 Complete the table by predicting: ● the boiling point of rubidium ● the atomic radius of potassium.  Describe the trend in the melting point of the GroupI elements down the group. Deduce the physical state of potassium at 60 °C. Explain your answer. Caesium is a radioactive element with a proton number of 55. Define proton number. State one industrial use of radioactive isotopes. Sodiumhydride, NaH, reacts with iron(oxide. Balance the equation for this reaction. Fe2O3 + 3NaH → Fe + NaOH Explain how this equation shows that iron(oxide is reduced. 
9. Metals  →  9.4. Reactivity series
8. The Periodic Table  →  8.1. Arrangement of elements
8. The Periodic Table  →  8.2. Group I properties
Open
4
The structure of malic acid is shown. C C H O O H H O C H C H O O H On the structure draw a circle around the alcohol functional group. Deduce the formula of malicacid to show the number of carbon, hydrogen and oxygen atoms. When malicacid is heated it forms compoundF. The structure of compoundF is shown. C C H O O H C C H O O H Explain why compoundF is described as unsaturated. CompoundF can form polymers. State the meaning of the term polymer. State the name of the polymer formed when ethene is polymerised. Ethanoic acid is a carboxylic acid. Describe the observations made when dilute ethanoicacid reacts with: magnesium litmus solution.  The graph shows how the pH changes when dilute ethanoicacid is added slowly to aqueous sodiumhydroxide. volume of dilute ethanoic acid added / cm3 pH Deduce the pH of the aqueous sodiumhydroxide before the addition of dilute ethanoicacid.  pH = Deduce the volume of dilute ethanoicacid added when the pH is neutral.  cm3 
11. Organic chemistry  →  11.7. Carboxylic acids
7. Acids, bases and salts  →  7.1. The characteristic properties of acids and bases
Open
5
Calciumoxide is made by the thermal decomposition of calciumcarbonate. State the meaning of the term thermal decomposition. Describe a test for calcium ions. test observations  Carbondioxide is produced when dilute hydrochloricacid reacts with calciumcarbonate. CaCO3 + 2HCl → CaCl 2 + CO2 + H2O Complete the diagram to show how to measure the volume of carbondioxide produced during this reaction. dilute hydrochloric acid calcium carbonate  Describe the effect of each of the following on the rate of reaction of dilute hydrochloricacid with calciumcarbonate. ● The concentration of hydrochloric acid is decreased. All other conditions stay the same. ● The temperature is increased. All other conditions stay the same.  Carbondioxide is also formed when the hydrocarbon C3H8 is completely combusted. State the meaning of the term hydrocarbon. The hydrocarbon C3H8 is called propane. Name the homologous series that propane belongs to. Name two substances formed by the incomplete combustion of propane. and 
6. Chemical reactions  →  6.2. Rate of reaction
12. Experimental techniques and chemical analysis  →  12.5. Identification of ions and gases
Open
6
This question is about water. The water in rivers often contains pollutants such as acids. Describe how universal indicator paper can be used to determine the pH value of the water. The diagram shows some of the stages in water treatment. impure water aeration tank mixing tank chlorine air purified water filter Air is blown through the aeration tank. Name the two gases that make up most of the air. and After aeration, the water still contains large insoluble particles. The filter is made up of fine sand and stones. Explain how the filter helps purify the water. Explain why chlorine is used in water treatment. Anhydrous cobalt(chloride is used to test for water. State the colour change in this test. from to 
10. Chemistry of the environment  →  10.1. Water
Open
7
Molten lead(bromide is electrolysed using carbon electrodes. State the products of this electrolysis at: the negative electrode the positive electrode.  State the name of another substance which can be used as an inert electrode. When aqueous magnesiumchloride is electrolysed using carbon electrodes, hydrogen gas is produced at the negative electrode. Complete the dot-and-cross diagram to show the electron arrangement in one molecule of hydrogen.  
4. Electrochemistry  →  4.1. Electrolysis
Open
8
This question is about elements in the Periodic Table. The table shows some properties of five elements, P, Q, R, S and T. element melting point / °C density in g / cm3 electrical conductivity of the solid atomic radius / nm P 7.86 very good 0.125 Q –7 3.12 does not conduct 0.114 R 8.90 very good 0.126 S –157 0.0035 does not conduct 0.110 T 1.54 very good 0.174 Use only the elements shown in the table to answer this question. State which two of the elements, P, Q, R, S and T, are covalent molecules. Give two reasons for your answer. elements and reason 1 reason 2  ElementT is on the left-hand side of the Periodic Table. Suggest whether its oxide is acidic or basic. Give a reason for your answer. Krypton is an element in GroupVIII of the Periodic Table. Explain, using ideas about electronic structure, why krypton is unreactive. Sodium is an element in GroupI of the PeriodicTable. Iron is a transition element. Iron has a higher melting point and higher boiling point than sodium. Give two other ways in which the properties of transition elements differ from the properties of GroupI elements.  The table compares the reactivity of four metals with dilute hydrochloricacid. metal reaction with dilute hydrochloric acid calcium reacts very rapidly copper no reaction iron reacts rapidly nickel reacts slowly Put the four metals in order of their reactivity. Put the least reactive metal first. least reactive most reactive  Hot iron reacts with steam. The reaction is reversible. Complete the equation by writing the symbol for a reversible reaction in the box. 3Fe + 4H2O Fe3O4 + 4H2  Steel is an alloy of iron. State the meaning of the term alloy. 
9. Metals  →  9.4. Reactivity series
8. The Periodic Table  →  8.1. Arrangement of elements
Open