GCSE OCR Chemistry B Paper 2 Automarked

#1. Calculate the relative formula mass of water. Hydrogen Aᵣ = 1, Oxygen Aᵣ = 16.

enter answer here...

#2. What is the formula for the polyatomic ion nitrate?

NH₄⁺

SO₄²⁻

SO₃²⁻

OH⁻

NO₃⁻

CO₃²⁻

#3. What is the formula for hydrochloric acid?

H₂SO₄

KOH

NaOH

HCL

HNO₃

Ca(OH)₂

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

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

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

#5. Temperature affects the rate of reaction. Which of the following is the correct description of what happens when temperature changes?

Rate of reaction is highest at very high and very low temperatures

As temperature increases, rate of reaction increases

As temperature increases, rate of reaction decreases

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

Select all that apply:

salt

electrons

oxygen

hydrogen

#7. Which of these are common properties of giant covalent materials?

Insoluble in water

High melting/boiling points

Low melting/boiling points

Conduct electricity

Soluble in water

Do not conduct electricity

#8. Determine the empirical formula for Cyanuric triazide - C₃N₁₂.

C₂N₄

C₄N₄

CN₄

CN

#9. Complete the equation: NaOH(aq) → Na⁺(aq) + ....

HO⁻(aq)

OH⁻(aq)

NO⁻(aq)

#10. What is the chemical symbol for potassium?

enter answer here...

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

NH₄⁺

OH⁻

SO₄²⁻

CO₃²⁻

NO₃⁻

SO₃²⁻

#12. Filtration and crystallisation are used to separate which types of materials?

separate soluble materials from insoluble materials

separate different types of liquids

separating soluble compounds

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

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

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

#14. What is the chemical symbol for magnesium?

enter answer here...

#15. Acids produce an excess of what when they dissolve in water?

hydroxide ions

hydrogen ions

carbonate ions

sulfate ions

#16. Covalent compounds typically form between which two types of material?

metal and non-metal

non-metal and non-metal

metal and metal

#17. How could we accurately monitor the rate of a reaction? ? Three answers

Select all that apply:

By measuring the changes in volume of reactants and products

By measuring the concentration of reactants and products throughout a reaction

By measuring the changes in mass of reactants and products

By measuring the temperature throughout a reaction

#18. What is the name of the phase change from liquid to gas?

sublimation

melting

condensation

freezing

deposition

evaporation/boiling

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

Select all that apply:

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

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 can be created and destroyed

atoms cannot be broken down into smaller parts

atoms cannot be created or destroyed

#20. Which of these reasons explains why temperature affects rate of reaction?

Reactant particles at higher temperatures move more quickly, collide more often and with enough energy to react

Reactant particles at lower temperatures are struck by rapidly moving electrons, causing the reaction to happen faster

Reactant particles are unaffected by temperature, but the bonds at higher temperatures become weaker leading to an increased rate of reaction

#21. Why did Ernest Rutherford's experiments with gold foil demonstrate that most of atoms consists of empty space?

Most of the atoms passed straight through the foil

Most of the atoms were deflected or bounced back

Most of the particles were destroyed when they met protons in the nucleus

#22. 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 cathode. Cu²⁺ + 2e →

CuO

SO₄²⁻

Cu

#23. Do non-metals usually have a high or low density?

High

Low

#24. What are ions?

atoms which have gained or lost electrons

atoms which have different numbers of neutrons

atoms which have different numbers of protons

#25. Which of these is the stationary phase in paper chromatography?

the ink

the paper

the solvent

#26. What is the formula for potassium oxide? ? you might need a periodic table to answer this question

enter answer here...

#27. Can strong and weak acids have the same pH?

not sure

no

yes

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

1 x 10⁻³

1 x 10⁻⁴

1 x 10⁻¹⁵

1 x 10⁻⁵

#29. What is the chemical symbol for silver?

enter answer here...

#30. Why is a spark often needed to start a combustion reaction?

It releases electrons from their shells and they rapidly ignite the fuel

It removes excess nitrogen from the surrounding area, making ignition easier

It provides the activation energy needed

#31. 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: Chlorine (Cl₂)

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

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

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

#32. Which of these is the mobile phase in paper chromatography?

the ink

the paper

the solvent

#33. What are negative ions called?

enter answer here...

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

Cathode: Sodium (Na) Anode: Hydroxide (OH⁻)

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

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

#35. Increasing the concentration of solutions increases the rate of reaction, why is this the case?

When solutions are more concentrated, the intermolecular forces become weaker and bonds are more easily broken

More collisions take place because there are more particles in the same volume

When solutions are dilute, there are more particles in the same volume

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

More soluble - shorter distance

More soluble - greater distance

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

Loss, Cathode

Gain, Cathode

Loss, Anode

Gain, Anode

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

A central nucleus containing protons and neutrons, surrounded by electrons

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

#39. Which description best describes an element?

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

contains only one type of atom

contains more than one type of atoms, chemically bonded together

#40. Fill in the blanks: Electrolysis is a process in which .......... energy from a .......... current supply is used to decompose electrolytes.

Electrical, Direct

Thermal, Direct

Electrical, Alternating

Thermal, Indirect

#41. Displacement reactions sometimes occur between a metal and a compound of a less reactive metal. Are these reactions endothermic or exothermic?

Exothermic

Endothermic

#42. Which of these best describes metallic bonding?

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.

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.

#43. What is the charge of a proton?

0

-1

+1

#44. Fresh water contains many different contaminants and so must be cleaned before it becomes potable. Which is the correct treatment path?

water from source --> chlorine added --> filtration tower --> sedimentation tank --> storage --> water pumped to homes

water from source --> sedimentation tank --> filtration tower --> chlorine added --> storage --> water pumped to homes

water from source --> filtration tower --> chlorine added --> water pumped to homes

#45. The table shows 3 substances and their melting points. Which type of substance is X?

compound

mixture

element

#46. What is the chemical symbol for calcium?

enter answer here...

#47. Which of the following descriptions matches the term molecular formula?

Is the sum of the relative atomic masses

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

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

#48. The table shows 3 substances and their melting points. What common substance, in particular, could substance Z be?

enter answer here...

#49. What is the formula for sodium hydroxide?

HCL

KOH

H₂SO₄

HNO₃

NaOH

Ca(OH)₂

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

Cl⁻(s)

Cl⁻(aq)

Cl⁻(l)

#51. In an experiment to measure the rate of photosynthesis of pondweed in a test tube, the number of bubbles (oxygen) produced per minute is used to determine the rate of reaction. What is this experiment actually measuring?

The volume of the products of the reaction

The mass of the products of the reaction

The concentration of the products of the reaction

The mass of the reactants of the reaction

The volume of the reactants of the reaction

#52. Why are metals malleable?

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

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

#53. Are metals usually good conductors of heat?

No

Yes

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

The simplest whole number ratio of atoms

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

The mean mass of an atom compared with carbon-12

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

solids

liquids

gases

#56. Why is there a minimum energy required for reactions to occur?

High energies cause spontaneous rearrangement of particles without impacts between them

High collision energies are more likely to break chemical bonds

#57. Why is diamond hard?

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

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

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

#58. Surface area to volume ratio affects rate of reaction. Why is that the case?

With higher surface area to volume ratio, there is more surface where collisions can take place

With lower surface area to volume ratio, objects are much hotter and travel faster

With higher surface area to volume ratio, the overall temperature of reactants is lower, this leads to increased collision impact when struck

#59. Which process can be used to separate water from dissolved salts, whilst keeping both substances?

enter answer here...

#60. True or false - Precipitation reactions can be either exothermic or endothermic.

True

False

#61. Which of the following are properties of ionic compounds?

conduct electricity as solids

high melting and boiling points

conduct electricity when molten or dissolved

usually insoluble

low melting and boiling points

usually soluble

#62. Why did the concentration of carbon dioxide in the atmosphere decrease after the oceans formed?

Carbon dioxide was split by photolysis, producing pure carbon which rained down as a solid.

Carbon dioxide dissolved into the oceans and sea organisms used carbon in their shells as calcium carbonate

Carbon dioxide escaped the atmosphere as the Earth's spin increased in speed, causing an increase the centrifugal force

#63. Determine the empirical formula for Cyclopentane - C₅H₁₀?

CH₂

CH₄

2CH

C₂H₂

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

enter answer here...

#65. Calcium nitrate contains the polyatomic ion NO₃⁻ (nitrate) and calcium. How many nitrate ions will be needed to make one molecule of calcium nitrate?

3

1

2

#66. Most ionic bonds are formed between which groups?

metals and non-metals

non-metals and non-metals

metals and metals

#67. When using inert electrodes to perform electrolysis with sodium sulfate solution, which products will be produced at the anode and cathode?

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

Cathode: Sodium (Na) Anode: Hydroxide (OH⁻)

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

#68. Which of the following are uses for paper chromatography?

Select all that apply:

identifying substances by calculating Rf values

identifying substances by comparing chromatogram patterns to patterns formed by known substances

distinguishing between pure and impure substances

separating insoluble solids

determining the boiling point of a substance

$fractional distillation diagram$

#69. This image shows the apparatus used during fractional distillation. What is function of the fractionating column?

contains glass rods - is hotter at bottom than top - only the desired liquid will reach the condenser

contains glass rods - is hotter at top than bottom - only the desired liquid will reach the condenser

contains glass rods - is the same temperature throughout - only the desired liquid will reach the condenser

#70. During a neutralisation reaction which salt is formed from hydrochloric acid?

borate

chloride

carbonate

sulfate

nitrate

#71. What is the boiling temperature of water?

66.5˚C

25˚C

30˚C

100˚C

55˚C

10˚C

#72. Which electrode would the ion Mg²⁺ migrate to during electrolysis?

Cathode

Neither

Anode

#73. Why did the amount of oxygen in the atmosphere increase over time?

Oxygen present in the Earth's mantle, seeped out over time and escaped via deep ocean ridges

Oxygen was released during the Great Oxidation Period from extensive volcanic activity

Plants and other organisms began to perform photosynthesis, producing oxygen gas

#74. Paper chromatography is used to separate which types of materials?

separating soluble compounds

separate different types of liquids

separate soluble materials from insoluble materials

#75. A soluble base is called?

an alkali

a biscuit

an antacid

#76. Calculate the relative formula mass of copper oxide (CuO) to 2 decimal places. Copper Aᵣ = 63.5, Oxygen Aᵣ = 16.

enter answer here...

#77. The melting point of gallium is 29.8˚C and the boiling point is 2204˚C. What state is gallium at 25˚C?

gas

solid

liquid

#78. Chemical reactions require a high enough collision energy for reactions to take place. What do we call the minimum amount of energy needed for a reaction?

Reactionary energy

The Introactive energy minimum

Activation energy

PR energy

#79. What is the freezing point of water?

0˚C

55˚C

25˚C

30˚C

66.5˚C

100˚C

#80. Which of the following are effects of climate change?

Select all that apply:

Extinctions of species unable to migrate or adapt to higher temperatures

Lower pH of oceans due to dissolving carbon dioxide producing carbonic acid

Rising ocean temperatures causing coral bleaching and other adverse effects

Rising sea levels due to ice in the south pole and in glaciers melting

More extreme weather events (stronger storms, rainfall and droughts)

#81. If covalent bonds are very strong, then why does water have a low melting point?

The bonds between hydrogen and oxygen are weaker than typical covalent bonds

There are only weak intermolecular forces between the molecules in water. The atoms remain bonded whilst the molecules become separated.

Water has a high melting point

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

distance moved by solvent x distance moved by spot

distance moved by solvent / distance moved by spot

distance moved by spot / distance moved by solvent

#83. What is the chemical symbol for chlorine?

enter answer here...

#84. Solutions of less than pH 7 are?

alkaline

neutral

acidic

#85. What is the charge of a neutron?

0

-1

+1

#86. What is the name of the apparatus used for distillation?

enter answer here...

#87. Which three particles are atoms composed of?

enter answer here...

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

No

Yes

#89. Which of the following descriptions matches the Aᵣ of an element?

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

The simplest whole number ratio of atoms

The mean mass of an atom compared with carbon-12

#90. Which human activities cause increases in the greenhouse gases - carbon dioxide and methane?

Select all that apply:

Livestock farming

Burning fossil fuels

Planting trees

GCSE OCR Chemistry B Paper 2

Good Luck!

Results

#1. Calculate the relative formula mass of water. Hydrogen Aᵣ = 1, Oxygen Aᵣ = 16.

#2. What is the formula for the polyatomic ion nitrate?

#3. What is the formula for hydrochloric acid?

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

#5. Temperature affects the rate of reaction. Which of the following is the correct description of what happens when temperature changes?

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

#7. Which of these are common properties of giant covalent materials?

#8. Determine the empirical formula for Cyanuric triazide - C₃N₁₂.

#9. Complete the equation: NaOH(aq) → Na⁺(aq) + ....

#10. What is the chemical symbol for potassium?

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

#12. Filtration and crystallisation are used to separate which types of materials?

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

#14. What is the chemical symbol for magnesium?

#15. Acids produce an excess of what when they dissolve in water?

#16. Covalent compounds typically form between which two types of material?

#17. How could we accurately monitor the rate of a reaction? ? Three answers

#18. What is the name of the phase change from liquid to gas?

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

#20. Which of these reasons explains why temperature affects rate of reaction?

#21. Why did Ernest Rutherford's experiments with gold foil demonstrate that most of atoms consists of empty space?

#22. 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 cathode. Cu²⁺ + 2e →

#23. Do non-metals usually have a high or low density?

#24. What are ions?

#25. Which of these is the stationary phase in paper chromatography?

#26. What is the formula for potassium oxide? ? you might need a periodic table to answer this question

#27. Can strong and weak acids have the same pH?

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

#29. What is the chemical symbol for silver?

#30. Why is a spark often needed to start a combustion reaction?

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

#32. Which of these is the mobile phase in paper chromatography?

#33. What are negative ions called?

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

#35. Increasing the concentration of solutions increases the rate of reaction, why is this the case?

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

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

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

#39. Which description best describes an element?

#40. Fill in the blanks: Electrolysis is a process in which .......... energy from a .......... current supply is used to decompose electrolytes.

#41. Displacement reactions sometimes occur between a metal and a compound of a less reactive metal. Are these reactions endothermic or exothermic?

#42. Which of these best describes metallic bonding?

#43. What is the charge of a proton?

#44. Fresh water contains many different contaminants and so must be cleaned before it becomes potable. Which is the correct treatment path?

#45. The table shows 3 substances and their melting points. Which type of substance is X?

#46. What is the chemical symbol for calcium?

#47. Which of the following descriptions matches the term molecular formula?

#48. The table shows 3 substances and their melting points. What common substance, in particular, could substance Z be?

#49. What is the formula for sodium hydroxide?

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

#51. In an experiment to measure the rate of photosynthesis of pondweed in a test tube, the number of bubbles (oxygen) produced per minute is used to determine the rate of reaction. What is this experiment actually measuring?

#52. Why are metals malleable?

#53. Are metals usually good conductors of heat?

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

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

#56. Why is there a minimum energy required for reactions to occur?

#57. Why is diamond hard?

#58. Surface area to volume ratio affects rate of reaction. Why is that the case?

#59. Which process can be used to separate water from dissolved salts, whilst keeping both substances?

#60. True or false - Precipitation reactions can be either exothermic or endothermic.

#61. Which of the following are properties of ionic compounds?

#62. Why did the concentration of carbon dioxide in the atmosphere decrease after the oceans formed?

#63. Determine the empirical formula for Cyclopentane - C₅H₁₀?

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

#65. Calcium nitrate contains the polyatomic ion NO₃⁻ (nitrate) and calcium. How many nitrate ions will be needed to make one molecule of calcium nitrate?

#66. Most ionic bonds are formed between which groups?

#67. When using inert electrodes to perform electrolysis with sodium sulfate solution, which products will be produced at the anode and cathode?

#68. Which of the following are uses for paper chromatography?

#69. This image shows the apparatus used during fractional distillation. What is function of the fractionating column?

#70. During a neutralisation reaction which salt is formed from hydrochloric acid?

#71. What is the boiling temperature of water?

#72. Which electrode would the ion Mg²⁺ migrate to during electrolysis?

#73. Why did the amount of oxygen in the atmosphere increase over time?

#74. Paper chromatography is used to separate which types of materials?

#75. A soluble base is called?

#76. Calculate the relative formula mass of copper oxide (CuO) to 2 decimal places. Copper Aᵣ = 63.5, Oxygen Aᵣ = 16.

#77. The melting point of gallium is 29.8˚C and the boiling point is 2204˚C. What state is gallium at 25˚C?