7 questions · 70 marks · ≈ 70 min
Use the Periodic Table to help you answer this question.
Name the element with atomic number 14.
Name the element in Group 2 and Period 3.
Name an element that is a liquid at room temperature.
Give the electronic configuration of an atom of phosphorus.
Give the formula of sodium sulfide.
Explain, in terms of electron configuration, why neon is unreactive.
This question is about gases in the atmosphere.
Which of these gases has the lowest percentage by volume in the atmosphere?
Choose your answer
argon
carbon dioxide
nitrogen
oxygen
When copper(II) carbonate is heated, copper(II) oxide and carbon dioxide form.
What is the name of this type of reaction?
Choose your answer
addition
decomposition
oxidation
substitution
Which colour change occurs when copper(II) carbonate is heated?
Choose your answer
blue to black
blue to orange
green to black
green to orange
Give the chemical equation for this reaction.
A student uses this apparatus to find the percentage of oxygen in a sample of air. gas syringe air conical flask wet iron filings The student leaves the apparatus until there is no further change in volume of gas in the syringe. These are the student’s results. volume of gas in flask and connecting tube in cm³ 280 volume of gas in syringe at start in cm³ 100 volume of gas in syringe at end in cm³ 27 Calculate the percentage of oxygen in the sample of air. Give your answer to two significant figures. percentage of oxygen = %
Explain why an increasing amount of carbon dioxide in the atmosphere is likely to cause a problem for the environment.
This question is about alcohols. Ethanol can be manufactured using two different methods.
Complete the equation for fermentation. C₆H₁₂O₆ → +
The table gives some information about the two methods. Hydration Fermentation Reagents ethene and steam aqueous glucose Catalyst enzymes in yeast Temperature in °C 300 Pressure in atmospheres 1 Rate of process fast slow Purity of product pure impure
Complete the table by giving the missing information.
Explain one advantage and one disadvantage of using fermentation rather than hydration to produce ethanol. You should use information from the table to help your answer. advantage disadvantage
Explain why fermentation needs to occur in the absence of air.
Propanol has this percentage composition by mass. C = 60.0% H = 13.3% O = 26.7%
Show by calculation that the empirical formula of propanol is C₃H₈O.
Draw the displayed formula of propanol.
A student does a titration to find the concentration of potassium hydroxide solution. This is the student’s method.
Give the name of the most suitable piece of apparatus to measure out 25.0 cm³ of potassium hydroxide solution.
Give the colour of methyl orange in potassium hydroxide solution and in dilute sulfuric acid. colour in potassium hydroxide solution colour in dilute sulfuric acid
State why the student places the conical flask on a white tile.
State why the student swirls the flask continuously.
State what is meant by the term concordant results.
The student finds that 15.00 cm³ of sulfuric acid of concentration 0.180 mol / dm³ neutralises 25.0 cm³ of potassium hydroxide solution. This is the equation for the reaction. 2KOH + H₂SO₄ → K₂SO₄ + 2H₂O Calculate the concentration of the potassium hydroxide solution. concentration = mol / dm³
This is the ionic equation for the reaction between an acid and an alkali. H+(aq) + OH−(aq) → H₂O(l) Explain why the OH− ion is a proton acceptor in this reaction.
When copper(II) sulfate solution is electrolysed, copper forms at the negative electrode. A student uses this apparatus to investigate the electrolysis of copper(II) sulfate solution
Describe how the student could test a sample of copper(II) sulfate solution to show that it contains copper(II) ions.
Describe how copper metal forms at the negative electrode.
State the appearance of the copper that forms on the negative electrode.
Oxygen forms at the positive electrode.
Give a test for oxygen.
Complete the half-equation for the formation of oxygen at the positive electrode. 2H₂O → + +
State why the formation of oxygen at the positive electrode is an oxidation reaction.
Ethanoic acid reacts with methanol to form an ester. The equation shows the displayed formulae for the reactants and products
Give the name of a suitable catalyst to increase the rate of this reaction.
State how you would know that an ester has formed.
Give the name of this ester.
The table shows the number of bonds in the reactants and the number of bonds in the products. Bond C H C C C O C O O H Number of bonds in reactants 6 1 2 1 2 Number of bonds in products 6 1 2 1 2
State which two bonds need to be broken in the reactants.
Explain why the enthalpy change in this reaction is approximately 0 kJ / mol.
Methane reacts with steam to form carbon monoxide and hydrogen. This is the equation for the reaction. CH₄(g) + H₂O(g) ⇌ CO(g) + 3H₂(g) ∆H = +206 kJ / mol
State why carbon monoxide is poisonous to humans.
Explain the effect, if any, on the yield of hydrogen at equilibrium when a nickel catalyst is used.
The reaction conditions for this reaction are a temperature of 700 °C and a pressure of 5 atmospheres.
The temperature of the reaction mixture is reduced to 600 °C, but the pressure is kept at 5 atmospheres. Explain the effect on the yield of hydrogen at equilibrium.
The pressure of the reaction mixture is reduced to 4 atmospheres, but the temperature is kept at 700 °C. Explain the effect on the yield of hydrogen at equilibrium.
Calculate the volume, in dm³, of methane gas at rtp needed to produce 6.6 tonnes of hydrogen gas. [at rtp, molar volume = 24 dm³ 1 tonne = 106 g] Give your answer in standard form. volume of methane = dm³