Which two gases will diffuse at the same rate, at the same temperature?
A student measures the time taken for 2.0 g of magnesium to dissolve in 50 cm3
of dilute sulfuric acid.
Which apparatus is essential to complete the experiment?
1 stop-clock
2 measuring cylinder
3 thermometer
4 balance
A chromatogram of a single substance T is shown.
X and Y are two different elements.
X and Y have the same number of nucleons.
Which statement about X and Y is correct?
The diagrams show the structures of three macromolecules P, Q and R.
Which dot-and-cross diagram shows the arrangement of outer shell electrons in a molecule of hydrogen chloride?
The equation for the reaction between barium chloride and dilute sulfuric acid is shown.
Methane and steam react in the presence of a catalyst.
0.5 mol of methane reacts completely with 0.5 mol of steam.
What is the volume of carbon monoxide and hydrogen produced, measured at room temperature and pressure?
A compound of element X has the formula Xâ‚‚O and a relative formula mass of 144.
What is element X?
The diagram shows the electrolysis of concentrated hydrochloric acid and concentrated aqueous sodium chloride using carbon electrodes.
At which electrodes is hydrogen produced?
The diagram shows the electrolysis of aqueous copper(II) sulfate using inert electrodes. Which arrow shows the movement of electrons in the circuit?
Which row identifies a chemical change and a physical change?
Which statements explain why increasing the concentration of a reactant increases the rate of reaction?
1 It increases the collision rate of particles.
2 It lowers the activation energy.
3 A greater proportion of the colliding molecules have the required activation energy.
4 There are more particles per unit volume.
When the colourless gas is heated, it forms the brown gas NOâ‚‚.
When the reaction mixture is cooled, the brown colour fades and turns back to colourless.
Which type of reaction is described by these observations?
Water is added to anhydrous copper(II) sulfate.
What happens during the reaction?
Which arrow on the energy level diagram shows the overall energy change for an endothermic reaction?
When a hydrogen–oxygen fuel cell is in operation, a different reaction happens at each electrode.
at the hydrogen electrode
at the oxygen electrode
The electrons that are lost at the hydrogen electrode travel through the external circuit to the oxygen electrode, where they are gained by oxygen and water.
A hydrogen–oxygen fuel cell is operated for a period of time and four moles of oxygen molecules are consumed.
Which mass of hydrogen is consumed?
The oxides of two elements, X and Y, are separately dissolved in water and the pH of each solution tested.
Which information about X and Y is correct?
An acid is neutralised by adding an excess of an insoluble solid base.
A soluble salt is formed.
How is the pure salt obtained from the reaction mixture?
Substance J takes part in a redox reaction.
In the reaction, J gains electrons.
Which statement is correct?
Elements in Group IV of the Periodic Table are shown.
carbon
silicon
germanium
tin
lead
What does not occur in Group IV as it is descended?
Which statement about acids is correct?
Which elements have both a high melting point and variable oxidation states?
Lithium, sodium and potassium are elements in Group I of the Periodic Table.
Chlorine, bromine and iodine are elements in Group VII of the Periodic Table.
Which row identifies the least dense of these elements in each group?
The reactions of metals P, Q, R and S are shown.
What is the order of reactivity of the metals?
The number of protons and the number of neutrons in the atoms of elements X, Y and Z are shown.
Which statement about the elements is correct?
Which diagram represents the arrangement of atoms in an alloy?
Three metal compounds, J, K and L, are heated using a Bunsen burner.
The results are shown.
J colourless gas produced, which relights a glowing splint
K colourless gas produced, which turns limewater milky
L no reaction
Which row identifies J, K and L?
Processes involved in the extraction of zinc are listed.
1 Heat zinc oxide with carbon.
2 Condense zinc vapour.
3 Vaporise the zinc.
4 Roast zinc ore in air.
In which order are the processes carried out?
Which process uses sacrificial protection to prevent steel from rusting?
Fertilisers are used to provide three of the elements needed for plant growth.
Which two compounds would give a fertiliser containing all three of these elements?
Which processes produce carbon dioxide?
1 respiration
2 photosynthesis
3 fermentation
4 combustion of hydrogen
Which reaction in the Contact process requires the use of a catalyst?\
What are the products when limestone (calcium carbonate) is heated strongly?
The structure of ester W is shown.
Ethene reacts with substance X to form ethanol.
What is X?
Alkenes can be produced by cracking large hydrocarbon molecules to form smaller hydrocarbon molecules.
The structures of some hydrocarbons are shown.
Which statement about the hydrocarbons is correct?
Ethane reacts with chlorine in the presence of ultraviolet light.
Which substances are produced in the reaction?
Which polymer structure has the same linkages as Terylene?