OCR A Level Chemistry B (Salters) Fundamentals of chemistry June 2017 question paper H433/01

What is a possible mass number of a magnesium isotope?

A 12

B 23.99

C 24

D 24.3

Your answer

An element forms ions with a charge of 3+.

What could be the electron configuration of the atoms of the element?

1s²2s²2p³ A

1s²2s²2p⁶3s²3p⁶3d¹4s² B

1s²2s²2p⁶3p¹ C

1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p³ D

Your answer

Some models of the structure of the atom are described below.

1 Atoms are spheres.

2 Atoms have a dense nucleus.

3 The electrons are arranged in shells.

4 Atoms have protons and electrons embedded in them.

Which row represents the historical sequence of these models, with the earliest first?

Your answer

Polymer X is –CH(OH)–CH(COOCH₃)–CH(OH)–CH(COOCH₃)–

What is the monomer of polymer X ?

A CH(OH)–CH(COOH)

B C(OH)=C(COOCH₃)–C(OH)=C(COOCH₃)

C CH(OH)=CH(COOCH₃)

D CH₂–CH(COOH)

Your answer

An engine runs on ethanol.

What would not be found in the exhaust from this engine?

A SO₂

B CO₂

C NO

D CO

Your answer

Which statement about testing for nitrate(V) ions is correct?

A They give off ammonia gas when warmed with sodium hydroxide solution.

B Ammonia is detected because it turns blue litmus paper red.

C Aluminium is used to reduce nitrate(V).

D Nitrate(V) ions are oxidised.

Your answer

Which process is not oxidation?

Your answer

Which statement about DNA is not true?

A DNA is a condensation polymer.

B Adenine and uracil join by 2 hydrogen bonds in DNA.

C Guanine and cytosine join by 3 hydrogen bonds in DNA.

D The backbone of DNA is made of phosphate and deoxyribose.

Your answer

Which statement describes the secondary structure of a protein?

A the types of amino acids present

B the sequence of the amino acids

C attractions between groups causing folding of the protein helix

D hydrogen bonds causing a helix or sheet

Your answer

A student is given the electrode potentials below.

The student sets up a cell from the two half cells.

Which statement is correct?

A The cell voltage is 1.14 V.

Cu²⁺ is reduced by Ag. B

Cu is oxidised by Ag +. C

Cu²⁺ is oxidised by Ag. D

Your answer

Which ion is coloured?

Zn²⁺ A

Sc³⁺ B

Ti³⁺ C

Ti⁴⁺ D

Your answer

What describes a substance with a high retention time in gas-liquid chromatography?

A high volatility

B high solubility in the stationary phase

C high affinity for the mobile phase

D non-polar molecules

Your answer

Why are many bond enthalpies described as averages ?

A They are averaged out over many molecules with different kinetic energies.

B They are averaged out over different compounds containing the same bond.

C They are the averages of the bond in liquid and gaseous compounds.

D They are average values from different data books.

Your answer

Which statement is correct about electronegativity ?

A It increases from left to right across a period.

B It increases down a group.

C It measures the negative charge on an atom.

D The smaller the electronegativity difference between two elements, the more likely the bond between them is ionic.

Your answer

Which one of these molecules has an overall dipole?

A CH₂F₂

B CF₄

C BF₃

D SF₆

Your answer

Which row gives correct statements for both distillation and heating under reflux?

Your answer

What is correct about a mass spectrum of a compound?

A It shows the atoms produced from the compound.

B It enables the M_r of the compound to be determined.

It has a small M+1 peak because of some²H atoms present in the compound. C

D The units of the x-axis are ‘mass’.

Your answer

Nitrogen dioxide reacts with carbon monoxide as in the equation below.

The mechanism is:

Which expression is the correct rate equation?

A Rate = k [NO₂] [CO]

C Rate = k [CO]

Your answer

What is correct for reactions involving enzymes?

A The enzyme works best at high temperature.

B The rate is zero order with respect to substrate at low substrate concentration.

C The half-life for the substrate is always constant.

D The rate is zero order with respect to substrate at high substrate concentration.

Your answer

Which pair will not react together?

A (CH₃)₃CCOCl and (CH₃)₃CNH₂

B CH₃COCl and CH₃OH

C (CH₃)₃N and CH₃COCl

D C₆H₅OH and (CH₃)₃CCOCl

Your answer

5.6 g of Fe (A_r = 56) and 4.0 g of S (A_r = 32) are heated in air until no further reaction occurs.

All the iron is converted to FeS and the rest of the sulfur forms SO₂.

What is the mass (in grams) of the sulfur dioxide formed?

A 1.6

B 4.0

C 8.0

D 10.4

Your answer

A student has 25 cm³ of a 0.014 mol dm^–3 solution. 24

How much water should be added to make the solution 0.010 mol dm^–3?

10 cm³ A

14 cm³ B

35 cm³ C

49 cm³ D

Your answer

What is the correct name of an isomer of pent-1-ene?

A cyclopentene

B pent-4-ene

C 1-methylbut-2-ene

D 3-methylbut-1-ene

Your answer

Which statement(s) connected with the greenhouse effect is/are correct?

1 The Earth radiates infrared radiation.

2 Solar energy heats the surface of the Earth.

3 Greenhouse gases absorb ultra violet radiation causing their bonds to vibrate more.

A 1, 2 and 3

B Only 1 and 2

C Only 2 and 3

D Only 1

Your answer

Which statement(s) about rusting is/are correct?

1 Rust contains Fe³⁺ ions.

2 Oxygen molecules are reduced during rusting.

3 The first step in rusting is Fe Fe³⁺ + 3e^–.

A 1, 2 and 3

B Only 1 and 2

C Only 2 and 3

D Only 1

Your answer

Some organic reagents are hydrolysed under either acidic or alkaline conditions.

Which row(s) show(s) the correct products of the hydrolysis reactions?

A 1, 2 and 3

B Only 1 and 2

C Only 2 and 3

D Only 1

Your answer

Chlorine is manufactured by the electrolysis of sodium chloride solution. The equation is shown below.

Give the half equation for the reaction at the negative electrode during electrolysis and explain why it is reduction.

Half-equation

A sodium chloride solution contains 24.0% of sodium chloride by mass.

1.0 tonne of this solution is electrolysed.

Calculate the mass of chlorine produced (in tonnes). Give your answer to an appropriate number of significant figures.

mass of chlorine =........ tonnes

Industries using chlorine are often located close to the electrolysis plant.

Why is the transportation of chlorine dangerous?

Chlorine reacts with alkanes to form chloroalkanes. This reaction begins with the formation of chlorine radicals.

Complete the mechanism below to show the movement of electrons and name the type of bond fission.

Type of bond fission........

Once the radicals have formed, they are highly reactive. Give the equations for two propagation steps that occur in the reaction of ethane with chlorine.

Chlorine radicals in the stratosphere act as homogeneous catalysts in the breakdown of ozone.

Give equations for the catalytic cycle. Use the equations to explain the terms homogeneous and catalyst.

Ozone is also broken down by radiation in the stratosphere.

The bond broken in this reaction has a bond enthalpy of +302 kJ mol^–1.

Calculate the wavelength (in m) of radiation required to break this bond.

Hydrogen chloride can be prepared by reacting potassium chloride with concentrated sulfuric acid.

Give the equation for the reaction.

The reaction in (e) is repeated with potassium iodide. The hydrogen iodide formed is oxidised to iodine and the sulfuric acid is reduced to hydrogen sulfide.

Give the oxidation states of the elements in the compounds.

iodine in HI........ iodine in I₂........

sulfur in H₂SO₄........ sulfur in H₂S........

Use these oxidation states to write a balanced equation for the reaction of HI with H₂SO₄

Equation

One suggested method of carbon capture and storage is reacting carbon dioxide with naturally occurring metal oxides in the Earth’s crust.

Magnesium oxide and calcium oxide could have formed when dolomite marble was subjected to high temperatures in the Earth.

Dolomite contains both calcium and magnesium compounds. A student says that magnesium and calcium have similar chemistry because they are close in the Periodic Table.

Comment on the student’s statement.

A student finds that magnesium carbonate decomposes at a lower temperature than calcium carbonate.

Suggest the reason for this in terms of the ions present.

Calculate the volume of carbon dioxide (in dm³) at 298 K and 95.0 kPa that could be captured (c) by reacting it with 1.00 kg of MgO.

* Strontianite is a mineral first found in 1790. It contained a new element, strontium.

The element was first thought to be barium, which was known at the time. However, strontium gave a red flame colour when heated and barium’s flame is green.

Explain how elements can give off coloured light when heated and how analysis of the light from strontium proved that it was a new element.

An important source of hydrogen is from the steam reforming reaction shown below.

The position of equilibrium can be changed by altering the conditions.

Complete the table to show the effects on the yield of hydrogen and the value of the equilibrium

2.00 moles of methane and 1.00 mole of steam are allowed to reach equilibrium in a 1.00 dm³ (b) container. At equilibrium 0.66 mole of steam remains.

Calculate a value for the equilibrium constant and give its units.

How does the sign of ∆_sysS relate to the equation for the reaction?

The entropy values for some of the gases in equation 33.1 are shown below.

Use the value of ∆_sysS and the entropy values in the table to calculate the entropy of H₂

entropy of H₂(g) =........ J K^–1 mol^–1

Calculate whether the forward reaction in equation 33.1 is feasible at 1000 K.

The steam reforming reaction shown in equation 33.1 makes hydrogen. Much of the hydrogen is used in the manufacture of ammonia.

Calculate the atom economy of the reaction in equation 33.1 when making hydrogen.

How is carbon monoxide described when it is formed alongside the required product (hydrogen)?

The carbon monoxide can be used in the exothermic water gas shift reaction.

The water gas shift reaction often takes place in the same industrial plant as steam reforming.

Suggest two advantages of the water gas shift reaction taking place with steam reforming.

Two possible representations for benzene (C₆H₆) are shown below.

Compare and explain the bond angles and bond lengths predicted by each structure.

The equation below shows the hydrogenation of cyclohexene.

When benzene is reacted with hydrogen to form cyclohexane the enthalpy change is found to be – 208 kJ mol^–1.

Explain why this data supports structure 1 rather than structure 2.

A student wants to synthesise a dye. The first step in the formation of the dye is shown below.

This is an electrophilic substitution reaction.

Give the conditions for the reaction and an equation to show how the electrophile is formed.

Equation for formation of the electrophile

Magnesium sulfate, MgSO₄, has a variety of uses in agriculture and in medicine.

It exists in the solid state as a hydrated salt, MgSO₄•xH₂O.

In order to find the value of x in the formula, a student follows the procedure below.

A known mass of magnesium sulfate crystals is dissolved in water. Aqueous sodium carbonate is added to precipitate magnesium carbonate, MgCO₃.

∆_hydH values for the ions in magnesium sulfate are given in the table below.

Fill in the missing species in the box and use the diagram to calculate ∆_LEH for magnesium sulfate.

∆ =........ kJ mol^–1

Strontium sulfate is much less soluble than magnesium sulfate.

Use ideas of hydration enthalpy to suggest an explanation.