GCSE OCR Chemistry A Papers 1 and 3 Automarked

#1. During electrolysis which electrode do anions and cations migrate to?

Anions to the anode, cations to the cathode

Anions to the cathode, cations to the anode

#2. The distance travelled by a spot is determined by the solubility of the compound. How does solubility impact distance travelled?

More soluble - greater distance

More soluble - shorter distance

#3. In aqueous solutions such as sodium chloride solution, there will be negatively charged ions from the salt (Cl⁻) as well as hydroxide ions (OH⁻). What is the rule that determines which will be discharged at the anode.

Always the other ions and never the hydroxide

Always the hydroxide, unless a halide (group 7) is present.

Always the hydroxide regardless of the other ions

#4. What is the approximate radius of an atom?

1 x 10⁻³

1 x 10⁻¹⁰

1 x 10⁻¹⁵

#5. Are non-metals usually good conductors of electricity?

Yes

No

#6. What is the chemical symbol for oxygen?

#7. When using inert electrodes to perform electrolysis with molten lead bromide, which products will be produced at the anode and cathode?

Cathode: Hydrogen (H₂) (g) Anode: Lead (Pb) (s)

Cathode: Bromine (Br₂) (g) Anode: Lead (Pb) (s)

Cathode: Lead (Pb) (s) Anode: Bromine (Br₂) (g)

#8. Why do both graphite and diamond have high melting points?

Many strong covalent bonds need to be broken in order to melt the solid forms of diamond and graphite.

All materials made of carbon have a high melting point, that is why carbon is added to iron to make steel.

#9. Fill in the blanks: Reduction refers to the …… of electrons and it occurs at the ……..

Loss, Cathode

Gain, Cathode

Gain, Anode

Loss, Anode

#10. What is graphene?

Graphene is a small section of a diamond

Graphene is the material that forms from the covalent bonding of oxygen and nitrogen

Graphene is a layer of graphite that is one atom thick

#11. When using inert electrodes to perform electrolysis with water acidified with sulfuric acid, which products will be produced at the anode and cathode?

Cathode: Hydroxide (OH⁻) Anode: Hydrogen (H₂)

Cathode: Hydrogen (H₂) Anode: Hydroxide (OH⁻)

Cathode: Hydrogen (H₂) Anode: Sulfate (SO₄²⁻)

#12. What is the formula for calcium hydroxide?

Ca(OH)₂

NaOH

HCL

H₂SO₄

HNO₃

KOH

#13. Which type of reaction takes in energy, making the surroundings cooler?

Endothermic

Exothermic

Ectothermic

#14. The table shows 3 substances and their melting points. Which types of substances could Y be?

Select all that apply:

element

mixture

compound

#15. Complete the equation: HCl (aq) → H⁺(aq) + …..

Cl⁻(l)

Cl⁻(aq)

Cl⁻(s)

#16. What state of matter has particles which are far apart and move around independently?

gases

liquids

solids

#17. Determine the empirical formula for Cyanuric triazide – C₃N₁₂.

CN

C₄N₄

C₂N₄

CN₄

#18. Complete the following equation describing a reaction with a metal and an acid: metal + acid → …. + ….

Select all that apply:

hydrogen

oxygen

electrons

salt

#19. Complete the following half equation for a reaction the cathode during electrolysis of molten zinc chloride. Zn²⁺ + ….. → Zn

e

2e

Zn

ZnO

#20. The graph shows a heating curve for substance X (red) and substance Y (blue). Is substance X a pure or impure substance?

Impure

Pure

#21. What state of matter has particles which are close together and move around each other?

gases

liquids

solids

#22. Which three particles are atoms composed of?

#23. What is the chemical symbol for copper?

#24. What is the approximate radius of a nucleus?

1 x 10⁻⁵

1 x 10⁻⁴

1 x 10⁻³

1 x 10⁻¹⁵

#25. Strong acids do what in water? ? two words

#26. What is the relative mass of a neutron?

1

1/1840

2

#27. Because mixtures contain more than one substance and each has its own melting point, mixtures melt in which way?

at a specific point

over a range of temperatures

#28. Why does graphite conduct electricity?

Because it has more protons than electrons, this gives it a positive charge and enables it to carry a charge

Because it has only three covalent bonds, leaving one delocalised electron from each atom. These electrons are able to carry the charge.

#29. Why is magnesium a better electrical conductor than sodium?

Group 1 sodium is less electrically conductive because it quickly forms impurities that prevent efficient conduction

Group 2 magnesium has two spare electrons to donate to the delocalised pool, whereas, sodium atoms only have one electron to donate. This means there are more electrons to carry the charge

#30. What is the equation for Rf values in paper chromatography?

distance moved by solvent / distance moved by spot

distance moved by spot / distance moved by solvent

distance moved by solvent x distance moved by spot

#31. What is the charge of a proton?

0

-1

+1

#32. Which description most accurately describes covalent bonding

electrons are transferred between atoms

electrons are shared between atoms

#33. Why are metals malleable?

Because metal atoms themselves are compressible and are moulded into shape

Because metal ions constantly break and reform their bonds, allowing the shape to be moulded

Because the layers of metal slide across each other, rather than breaking the bonds between ions

#34. H₂SO₄(aq) + Na₂O(s) → …. + ….

Select all that apply:

2H₂O (l)

H₂O (l)

Na₂SO₄(aq)

MgOH

NaOH

#35. What are giant covalent structures?

a structure where each atom has a covalent bond to its neighbour

Ionically bonded substances such as sodium bromide

a compound which contains atoms covalently bonded together, but with weak intermolecular forces between molecules

#36. Which of the following describes the Plum Pudding Model of atomic structure?

A central nucleus containing protons and neutrons, surrounded by electrons at discrete energy levels (shells)

A mass of positively charged material with negatively charged electrons distributed throughout it

#37. Which of the following descriptions matches the Mᵣ of a compound?

The mean mass of an atom compared with carbon-12

The sum of the relative atomic masses of all of the atoms or ions in its formula

The simplest whole number ratio of atoms

#38. A soluble base is called?

an alkali

a biscuit

an antacid

#39. What is the formula for the polyatomic ion carbonate?

NH₄⁺

OH⁻

NO₃⁻

SO₄²⁻

CO₃²⁻

SO₃²⁻

#40. Which of these is a problem with dot and cross diagrams?

The model shows the atoms as being too far apart and there are no sticks

The model does not show that the ions will be constantly vibrating

They do not show how the structure formed and suggest that the electrons in different atoms are different, but they are actually the same

#41. Neutralisation reactions which occur between an acid and a base are always:

Endothermic

Exothermic

#42. Why is diamond hard?

Diamond is hard because it is made of ionically bonded carbon atoms.

Diamond is hard because carbon atom is covalently bonded to 4 other carbon atoms, in a tetrahedral arrangement.

Diamond is hard because it is composed of particular isotopes of carbon with extra neutrons, making the material more dense

#43. Reaction profiles are used to show the energy transfers during reactions. Which type of reaction is shown in this reaction profile?

Exothermic

Ectothermic

Endothermic

Mesothermic

#44. Which of the following descriptions matches the term empirical formula?

Represents the actual number of atoms of each element in a molecule

Is the sum of the relative atomic masses

Represents the simplest integer ratio of atoms or ions of each element in a compound

#45. Fractional distillation is used to separate which types of materials?

separate soluble materials from insoluble materials

separating soluble compounds

separate different types of liquids

#46. Which of these best describes metallic bonding?

Metal atoms share their electrons in order to fill their electron shells, this causes an attraction between the positive nuclei and shared electrons.

Metal atoms lose their electrons to non-metal atoms which then creates positive and negative ions which are attracted by electrostatic attraction.

Metal atoms lose their electrons to a delocalised pool and all of the metal ions are mutually attracted to the delocalised pool, holding all of the ions together.

#47. What type of substance is pure gold (Au)?

Mixture

Element

Compound

#48. Which of the following was the Rutherford Model of atomic structure?

A mass of positively charged material with negatively charged electrons distributed throughout it

A central nucleus containing protons and neutrons, surrounded by electrons

#49. What is the chemical symbol for sodium?

#50. During a neutralisation reaction which salt is formed from nitric acid?

Sulfate

Chloride

Carbonate

Borate

Nitrate

#51. Why is graphite softer than diamond?

Graphite is actually harder than diamond

Graphite is arranged in sheets with weak intermolecular forces holding them together. These can easily slide, making graphite soft.

Graphite is softer because the covalent bonds are weaker between atoms of carbon in graphite than in diamond

#52. Since metallically bonded atoms have a delocalised pool of electrons, these electrons are able to conduct ……

Select all that apply:

Electricity

Heat

Sound

Electromagnetic waves

#53. Solutions of pH 7 are?

alkaline

acidic

neutral

#54. Which of the following are weak acids?

Select all that apply:

boric acid

ethanoic acid

nitric acid

carbonic acid

hydrochloric acid

sulfuric acid

#55. Complete the equation: H⁺(aq) + OH⁻(aq) → ….

OH₂(aq)

CO₂(g)

H₂O(l)

2H₂O(l)

Remember:

acids produce an excess of hydrogen ions

alkalis produce an excess of hydroxide ions

hydrogen ions and hydroxide ions come together to make water which is neutral.

#56. What is the chemical symbol for iron?

#57. Can compounds be pure, for example, carbon dioxide?

no

yes

#58. Ernest Rutherford fired positive particles at a thin gold foil and showed that most of atoms is empty space. Which particles did he fire at the gold foil?

alpha particles

gamma rays

beta particles

#59. Which description best describes mixtures?

contains more than one type of atoms, chemically bonded together

contains only a particular type of atoms

contains more than one type of atoms, but not chemically bonded together

#60. What is the chemical symbol for phosphorus?

#61. What is the formula for the polyatomic ion ammonium?

SO₄²⁻

OH⁻

CO₃²⁻

NH₄⁺

SO₃²⁻

NO₃⁻

#62. What temperature is the boiling point of water?

#63. What is the chemical symbol for potassium?

#64. What is the relative mass of a proton?

1/1840

2

1

#65. What is the symbol for relative atomic mass?

Gᵣ

Mᵣ

AMᵣ

Aᵣ

#66. In aqueous solutions such as sodium chloride solution, there will be positively charged ions from the salt (Na⁺) as well as hydrogen ions (H⁺). What is the rule that determines which will be discharged at the cathode.

The least reactive ions

Always the ions from the salt e.g. Na⁺

The most reactive ions

#67. Alkalis produce an excess of what when they dissolve in water?

sulfite ions

hydroxide ions

sulfate ions

hydrogen ions

#68. What is the formula for sodium hydroxide?

HCL

HNO₃

NaOH

Ca(OH)₂

KOH

H₂SO₄

#69. Complete the following equation describing a neutralisation reaction with a metal oxide: metal oxide + acid → …. + ….

Select all that apply:

water

a different acid

electrons

positrons

salt

#70. Copper can be purified using electrolysis of copper sulfate solution. For this process we use the setup in the image below. Complete the half equation for the reaction at the anode. Cu → ….. + …..

SO₃²⁻ + 2e

Cu⁺ + e

Cu²⁺ + 2e

#71. What state of matter has particles which are close together and vibrate around fixed positions?

liquids

gases

solids

#72. What is the freezing point of water?

66.5˚C

25˚C

55˚C

30˚C

100˚C

0˚C

#73. Which types of atoms can be found in a pure piece of gold?

Select all that apply:

trace amounts of other elements

carbon atoms

gold atoms

#74. What is the name of the phase change from gas to solid?

condensation

freezing

deposition

melting

sublimation

evaporation/boiling

#75. What method can we use to separate multiple types of liquids?

#76. When using inert electrodes to perform electrolysis with copper chloride solution, which products will be produced at the anode and cathode?

Cathode: Copper (Cu) Anode: Hydrogen (H₂)

Cathode: Copper (Cu) Anode: Chlorine (Cl₂)

Cathode: Copper (Cu) Anode: Chlorine (OH⁻)

Cathode: Hydrogen (H₂) Anode: Chlorine (Cl₂)

#77. Complete the equation: H₂SO₄(aq) + ZnO(s) → …. + ….

Select all that apply:

HZnO₄ (s)

ZnSO₄ (aq)

H₂SO₄ (aq)

H₂SO₄ (l)

H₂O (l)

#78. After paper chromatography has been carried out, the paper is known as?

a chromatogram

a still

a wet piece of paper

#79. What do group one atoms do when they bond ionically with group 7 atoms?

gain two electrons

lose one electron

lose two electrons

gain one electron

#80. Can Rf values be higher than 1?

Under certain conditions

Yes

No

#81. What is an electrolyte?

An ionic compound in a molten or dissolved state

A solvent such as water

A covalent compound in a molten or dissolved state

#82. What is a solution called when it contains the maximum amount of solute that can dissolve in a solvent at a particular temperature?

flaccid

dilute

saturated

#83. What is the chemical symbol for helium?

#84. Which of the following things were hypothesised by John Dalton in 1805? ? select 4 answers

Select all that apply:

atoms can be created and destroyed

atoms are hard cubes that can be broken down into protons, neutrons and electrons

all matter is made up of tiny spheres called atoms

atoms in elements are identical, but elements have different types of atoms

atoms cannot be broken down into smaller parts

atoms cannot be created or destroyed

#85. Which of these descriptions best describes fullerenes?

Fullerenes are a group of extremely hard non-metal substances that are typically found deep underground.

Fullerenes are tubes or balls of carbon atoms with each carbon covalently bonded to three other carbons.

Fullerenes are the same as simple molecular compounds

#86. What is the word equation for photosynthesis? ? In some examples you might also see sunlight and chlorophyll above and below the arrow.

carbon dioxide + water → glucose + oxygen

carbon monoxide + water → glucose + oxygen

silicon dioxide + water → glucose + oxyen

#87. Chlorine has two stable isotopes, ³⁵Cl (75.77%) and ³⁷Cl (24.23%). Calculate the Aᵣ of chlorine to 2 decimal places.

#88. Determine the empirical formula for Cyclopentane – C₅H₁₀?

CH₂

2CH

CH₄

C₂H₂

#89. Which of these is a problem with metallic models?

The model does not show that the ions will be constantly vibrating

They do not show how the structure formed and suggest that the electrons in different atoms are different, but they are actually the same

The model shows the atoms as being too far apart and there are no sticks

#90. What is the name of the phase change from solid to gas?

sublimation

evaporation/boiling

deposition

freezing

melting

condensation

GCSE OCR Chemistry Papers 1 and 3

Results

#1. During electrolysis which electrode do anions and cations migrate to?

#2. The distance travelled by a spot is determined by the solubility of the compound. How does solubility impact distance travelled?

#3. In aqueous solutions such as sodium chloride solution, there will be negatively charged ions from the salt (Cl⁻) as well as hydroxide ions (OH⁻). What is the rule that determines which will be discharged at the anode.

#4. What is the approximate radius of an atom?

#5. Are non-metals usually good conductors of electricity?

#6. What is the chemical symbol for oxygen?

#7. When using inert electrodes to perform electrolysis with molten lead bromide, which products will be produced at the anode and cathode?

#8. Why do both graphite and diamond have high melting points?

#9. Fill in the blanks: Reduction refers to the …… of electrons and it occurs at the ……..

#10. What is graphene?

#11. When using inert electrodes to perform electrolysis with water acidified with sulfuric acid, which products will be produced at the anode and cathode?

#12. What is the formula for calcium hydroxide?

#13. Which type of reaction takes in energy, making the surroundings cooler?

#14. The table shows 3 substances and their melting points. Which types of substances could Y be?

#15. Complete the equation: HCl (aq) → H⁺(aq) + …..

#16. What state of matter has particles which are far apart and move around independently?

#17. Determine the empirical formula for Cyanuric triazide – C₃N₁₂.

#18. Complete the following equation describing a reaction with a metal and an acid: metal + acid → …. + ….

#19. Complete the following half equation for a reaction the cathode during electrolysis of molten zinc chloride. Zn²⁺ + ….. → Zn

#20. The graph shows a heating curve for substance X (red) and substance Y (blue). Is substance X a pure or impure substance?

#21. What state of matter has particles which are close together and move around each other?

#22. Which three particles are atoms composed of?

#23. What is the chemical symbol for copper?

#24. What is the approximate radius of a nucleus?

#25. Strong acids do what in water? ? two words

#26. What is the relative mass of a neutron?

#27. Because mixtures contain more than one substance and each has its own melting point, mixtures melt in which way?

#28. Why does graphite conduct electricity?

#29. Why is magnesium a better electrical conductor than sodium?

#30. What is the equation for Rf values in paper chromatography?

#31. What is the charge of a proton?

#32. Which description most accurately describes covalent bonding

#33. Why are metals malleable?

#34. H₂SO₄(aq) + Na₂O(s) → …. + ….

#35. What are giant covalent structures?

#36. Which of the following describes the Plum Pudding Model of atomic structure?

#37. Which of the following descriptions matches the Mᵣ of a compound?

#38. A soluble base is called?

#39. What is the formula for the polyatomic ion carbonate?

#40. Which of these is a problem with dot and cross diagrams?

#41. Neutralisation reactions which occur between an acid and a base are always:

#42. Why is diamond hard?

#43. Reaction profiles are used to show the energy transfers during reactions. Which type of reaction is shown in this reaction profile?

#44. Which of the following descriptions matches the term empirical formula?

#45. Fractional distillation is used to separate which types of materials?

#46. Which of these best describes metallic bonding?

#47. What type of substance is pure gold (Au)?

#48. Which of the following was the Rutherford Model of atomic structure?

#49. What is the chemical symbol for sodium?

#50. During a neutralisation reaction which salt is formed from nitric acid?

#51. Why is graphite softer than diamond?

#52. Since metallically bonded atoms have a delocalised pool of electrons, these electrons are able to conduct ……

#53. Solutions of pH 7 are?

#54. Which of the following are weak acids?

#55. Complete the equation: H⁺(aq) + OH⁻(aq) → ….

#56. What is the chemical symbol for iron?

#57. Can compounds be pure, for example, carbon dioxide?

#58. Ernest Rutherford fired positive particles at a thin gold foil and showed that most of atoms is empty space. Which particles did he fire at the gold foil?

#59. Which description best describes mixtures?

#60. What is the chemical symbol for phosphorus?

#61. What is the formula for the polyatomic ion ammonium?

#62. What temperature is the boiling point of water?

#63. What is the chemical symbol for potassium?

#64. What is the relative mass of a proton?

#65. What is the symbol for relative atomic mass?

#66. In aqueous solutions such as sodium chloride solution, there will be positively charged ions from the salt (Na⁺) as well as hydrogen ions (H⁺). What is the rule that determines which will be discharged at the cathode.

#67. Alkalis produce an excess of what when they dissolve in water?

#68. What is the formula for sodium hydroxide?

#69. Complete the following equation describing a neutralisation reaction with a metal oxide: metal oxide + acid → …. + ….

#70. Copper can be purified using electrolysis of copper sulfate solution. For this process we use the setup in the image below. Complete the half equation for the reaction at the anode. Cu → ….. + …..

#71. What state of matter has particles which are close together and vibrate around fixed positions?

#72. What is the freezing point of water?

#73. Which types of atoms can be found in a pure piece of gold?

#74. What is the name of the phase change from gas to solid?

#75. What method can we use to separate multiple types of liquids?

#76. When using inert electrodes to perform electrolysis with copper chloride solution, which products will be produced at the anode and cathode?

#77. Complete the equation: H₂SO₄(aq) + ZnO(s) → …. + ….

#78. After paper chromatography has been carried out, the paper is known as?