No questions found
Which statement about a solid, a liquid or a gas is correct?
560
558
532
Which diagram represents a mixture of compounds?
568
523
558
Four ions are listed. $$\text{N}^{3-}\quad \text{Al}^{3+}\quad \text{Li}^{+}\quad \text{Cl}^{-}$$ Which pair of ions have the same electronic configuration?
558
592
573
Which statement about isotopes is correct?
504
538
543
Which statement about the ions formed by the elements in Group VII of the Periodic Table is correct?
527
528
564
Which row describes the properties of potassium bromide? [Table_1]
512
554
520
Which statement explains why graphite is used as a lubricant?
567
532
544
What is the balanced equation for the reaction between magnesium and dilute sulfuric acid?
536
560
545
The relative atomic mass, $A_r$, of an element is the average mass of the isotopes of that element compared to another particle.
Which particle is used for this comparison?
592
544
529
The equations for two reactions are shown.
equation 1\ C + CO_2 \rightarrow x\ CO
equation 2\ 2C_2H_6 + 7O_2 \rightarrow 4CO_2 + y\ H_2O
Which row shows the value of \(x\), the value of \(y\) and the equations that are for redox reactions?
[Table_1]
552
595
501
Concentrated aqueous sodium chloride is electrolysed using graphite electrodes. What is the product formed at the cathode?
573
585
534
Which row describes the changes that occur when metals burn in oxygen? [Table_1]
568
531
572
When calcium carbonate is heated strongly, carbon dioxide gas is produced. Which words describe the type of change that occurs?
537
587
509
Which row about a hydrogen–oxygen fuel cell is correct?
[Table_1]
599
600
557
Which list contains \textit{only} chemical changes?
562
532
559
Excess calcium carbonate is added to 50 cm^3 of dilute hydrochloric acid of different concentrations in two separate experiments.
The volume of gas produced in experiment 1 and in experiment 2 is measured every 30 seconds.
The results are shown.
[Table_1]
Table:
| experiment | concentration of hydrochloric acid in mol/dm^3 | volume of gas after 30 seconds in cm^3 | volume of gas after 60 seconds in cm^3 | final volume of gas in cm^3 |
|-----------|--------------------------------------------|-----------------------------------|---------------------------------|-----------------------------|
| 1 | 0.20 | 55 | 99 | 120 |
| 2 | 0.10 | 26 | 50 | 59 |
Which diagram represents the data collected?
518
545
527
An experiment is set up as shown. The mass of the conical flask and its contents is measured at 30-second intervals.
50\, \text{cm}^3 \text{ dilute hydrochloric acid}
\text{1 g calcium carbonate}
\text{balance}
Which statement about the reaction and changes to the reaction conditions is correct?
527
555
565
Which reaction is reversible?
579
538
560
Silver oxide reacts with magnesium to make silver and magnesium oxide.
$$\text{Ag}_2\text{O} + \text{Mg} \rightarrow 2\text{Ag} + \text{MgO}$$
Which substance is oxidised in this reaction?
547
533
581
Compound X dissolves in water to form an aqueous solution. Methyl orange is added to aqueous compound X. The methyl orange turns red. What is compound X?
560
541
512
Dilute hydrochloric acid reacts with aqueous sodium hydroxide in a neutralisation reaction. Which two ions are involved in this neutralisation reaction?
532
521
568
The table shows some properties of some of the elements in Group I of the Periodic Table. [Table_1: \text{Element table}]\n\nRubidium is also an element in Group I of the Periodic Table.\n\nWhich row describes the properties of rubidium? [Table_2: \text{Options table}]
579
556
583
Copper(II) sulfate crystals are blue. They are made by adding an excess of copper(II) oxide to sulfuric acid. The mixture is heated and stirred. The mixture is then filtered and the filtrate is allowed to evaporate, leaving blue crystals. Why is filtration necessary?
564
543
565
Which barium salts are soluble in water?
1. barium carbonate
2. barium chloride
3. barium nitrate
4. barium sulfate
506
587
549
Which statement about the properties of elements in Group I or in Group VII is correct?
518
598
564
Rubidium and strontium are both in Period 5 of the Periodic Table. Rubidium is in Group I. Strontium is in Group II. Which statement about these elements is correct?
510
540
522
A company needs a metal with a low density which resists corrosion and is a good electrical conductor.
Which metal should it use?
516
600
516
Which statement about stainless steel is correct?
543
547
518
Which statements explain why a water tap made of steel is electroplated with copper?
1. It improves the conductivity of the tap.
2. It improves the tap’s resistance to corrosion.
3. It increases the density of the tap.
526
582
504
The table shows the results of separately heating four metals with oxides of different metals.
The four metals are iron, copper, magnesium and Y.
The results are shown.
[Table_1]
What is the order of reactivity of the metals, least reactive first?
532
576
578
Which metal is most easily obtained from its ore?
554
504
551
Why is distilled water used in chemical experiments rather than tap water?
546
569
522
Which type of compound is also the name of a homologous series?
533
526
570
The fractional distillation of petroleum is shown. Which fraction is the least volatile?
566
540
574
Which formula represents an unsaturated hydrocarbon?
594
594
571
The structure of an organic compound is shown. The compound is tested separately with thymolphthalein and with aqueous bromine. Which row describes the final colour observed for each test? [Table_1]
559
508
513
Which statement describes methane?
587
547
538
Which row explains why plastics such as poly(ethene) cause pollution? [Table_1]
511
577
536
Two experiments are described.
experiment 1: A large mass of copper(II) sulfate is stirred into a beaker of water. After a few minutes, undissolved crystals are visible on the bottom of the beaker.
experiment 2: Sea water is distilled. Distilled water and solid impure salt are separated into two containers.
Which statement is correct?
539
590
502
An aqueous sample of X is heated with aqueous sodium hydroxide and small pieces of aluminium. A gas is produced which turns damp red litmus paper blue.
Aqueous sodium hydroxide is added to a second aqueous sample of X. A pale green precipitate is observed.
What is X?
518
597
544
