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Oxygen and fluorine are gaseous elements next to each other in the Periodic Table.
Under the same conditions of temperature and pressure, oxygen diffuses ......1...... than fluorine because its ......2...... is less than that of fluorine.
Which words correctly complete gaps 1 and 2?
[Table_1]
512
552
523
The diagrams show four pieces of laboratory equipment.
Which equipment is essential to find out if dissolving a salt in water is an exothermic process?
587
590
580
How many neutrons are present in the atom $^{45}_{21}X$?
566
594
543
Two naturally occurring isotopes of oxygen are $^{16}\text{O}$ and $^{17}\text{O}$.
Which statement is correct?
560
526
559
How many electrons are used to form covalent bonds in a molecule of methanol, CH$_3$OH?
551
556
516
Potassium bromide and methanol are both compounds. Their melting points are different. Which row is correct?
[Table_1]
542
552
525
Which gas sample contains the smallest number of molecules?
580
574
507
The equation for the reaction between calcium carbonate and dilute nitric acid is shown.
CaCO$_3$(s) + 2HNO$_3$(aq) → Ca(NO$_3$)$_2$(aq) + CO$_2$(g) + H$_2$O(l)
25g of calcium carbonate is reacted with an excess of dilute nitric acid.
Which mass of calcium nitrate and which volume of carbon dioxide is produced at room temperature and pressure?
525
582
531
The formulae of some ions are shown.
[Table_1]
Which formula is not correct?
524
586
579
Concentrated aqueous copper(II) chloride is electrolysed using copper electrodes as shown.
What happens to the mass of each electrode during this process?
587
535
549
The diagram shows a circuit used to electrolyse aqueous copper(II) sulfate.
Which arrows indicate the movement of the copper ions in the electrolyte and of the electrons in the external circuit?
582
588
520
Hydrogen peroxide, $\text{H--O--O--H}$, decomposes to form water and oxygen.
$$2\text{H}_2\text{O}_2(g) \rightarrow 2\text{H}_2\text{O}(g) + \text{O}_2(g)$$
The bond energies are shown in the table. The reaction is exothermic.
[Table_1]
What is the energy change for the reaction?
514
512
575
The equation for the formation of ammonia is shown.
$$\text{N}_2 + 3\text{H}_2 \rightarrow 2\text{NH}_3$$
The energy level diagram for the reaction is shown.
What is the energy change for the reaction?
544
513
529
The rate of reaction between magnesium ribbon and 2 mol/dm3 hydrochloric acid at 25°C to produce hydrogen gas is measured.
In another experiment, either the concentration of the hydrochloric acid or the temperature is changed. All other conditions are kept the same.
Which conditions increase the rate of reaction?
505
501
506
Methanol is prepared by the reversible reaction shown.
$$ \text{CO(g) + 2H}_2\text{(g)} \rightleftharpoons \text{CH}_3\text{OH(g)} $$
The forward reaction is exothermic.
Which conditions produce the highest equilibrium yield of methanol?
[Table_1]
501
539
534
The thermite reaction can be used to produce iron from iron(III) oxide. The equation for the reaction is shown.
$$2Al + Fe_2O_3 \rightarrow 2Fe + Al_2O_3$$
Which statements about this reaction are correct?
1. Aluminium is the oxidising agent.
2. Aluminium is less reactive than iron.
3. Electrons are transferred from aluminium to iron.
4. The iron in the iron(III) oxide is reduced.
552
510
579
In which row are the oxides correctly identified?
[Table_1: See image for table]
571
531
531
When dilute sulfuric acid is added to solid X, a colourless solution is formed and a gas is produced.
What is X?
546
581
582
A few drops of methyl orange are added to a reaction mixture.
During the reaction, a gas is produced and the methyl orange turns from red to orange.
What are the reactants?
562
554
536
Some general rules for the solubility of salts in water are listed.
• Carbonates are insoluble (except ammonium carbonate, potassium carbonate and sodium carbonate).
• Chlorides are soluble (except lead(II) chloride and silver chloride).
• Nitrates are soluble.
• Sulfates are soluble (except barium sulfate, calcium sulfate and lead(II) sulfate).
Which substances produce an insoluble salt when aqueous solutions of them are mixed?
535
577
540
Elements in Group I of the Periodic Table react with water.
Which row describes the products made in the reaction and the trend in reactivity of the elements?
[Table_1]
562
555
546
The equation shows the reaction between a halogen and aqueous bromide ions.
$$X_2 + 2Br^- \rightarrow 2X^- + Br_2$$
......1...... ......2...... ......3......
Which words complete gaps 1, 2 and 3?
539
576
509
An inert gas R is used to fill weather balloons.
Which descriptions of R are correct?
[Table 1]
532
562
526
Heating copper(II) carbonate produces copper(II) oxide and carbon dioxide.
Heating the copper(II) oxide formed with carbon produces copper.
Which processes are involved in this conversion of copper(II) carbonate to copper?
586
542
528
Four metals, W, X, Y and Z, are separately reacted with water and dilute hydrochloric acid. The results are shown.
[Table_1]
What is the order of reactivity of the four metals starting with the least reactive?
561
571
550
Which statement about the uses of metals is not correct?
508
516
541
Bauxite contains aluminium oxide.
Aluminium is extracted from aluminium oxide by electrolysis.
Why is cryolite added to the electrolytic cell used to extract aluminium?
573
529
549
Which statement about the Haber process is correct?
584
562
594
Which statements about sulfur dioxide pollution are correct?
1. It increases the pH of rivers.
2. It damages limestone buildings.
3. It causes respiratory problems.
540
567
525
Argon is a noble gas used to fill light bulbs.
What is the approximate percentage of argon in air?
524
538
556
The diagrams show experiments involving the rusting of iron. A student predicted the following results.
1. In tube P, the iron nails rust.
2. In tube Q, the iron nails do not rust.
3. In tube R, the iron nails do not rust.
Which predictions are correct?
522
556
556
In the carbon cycle, which two processes add carbon dioxide to the atmosphere?
583
599
564
Which statement about sulfur or one of its compounds is correct?
566
592
574
What is not a use of lime?
537
587
564
Which equation representing a reaction of methane is correct?
537
563
580
Which two compounds are molecules which both contain a double bond?
543
536
572
Ethanol can be formed by:
1. fermentation
2. reaction between steam and ethene.
Which of these processes use a catalyst?
[Table_1]
585
575
516
Ethanol is manufactured from ethene. What is an advantage of this process?
588
572
518
Which reaction can be used to make ethanoic acid?
545
569
591
The structure of an addition polymer is shown. Which monomer is used to make this polymer?
533
521
572
