Hydrocarbons in crude oil and natural gas.
How is crude oil classified as a resource?
A) It is a renewable resource that replenishes quickly.
B) It is an infinite resource that will never run out.
C) It is a finite resource found in rocks.
D) It is a resource created from atmospheric gases.
C) It is a finite resource found in rocks.
Which of the following properties of hydrocarbons depends on the size of their molecules?
A) Boiling point
B) Electrical conductivity
C) Solubility in water
D) Whether they are magnetic
A) Boiling point
Alkanes, which are the main type of hydrocarbon in crude oil, are molecules made up of which two types of atoms?
A) Carbon and Oxygen
B) Hydrogen and Nitrogen
C) Carbon and Hydrogen
D) Hydrogen and Oxygen
C) Carbon and Hydrogen
During the combustion of hydrocarbon fuels, the carbon and hydrogen in the fuels are oxidised. What does it mean for these elements to be oxidised in this process?
A) They lose energy and become less reactive.
B) They react with oxygen from the air.
C) They break down into individual atoms.
D) They turn into solid substances.
B) They react with oxygen from the air.
Where do the sulfur compounds sometimes found in hydrocarbon fuels primarily originate?
A) They are naturally present in the crude oil from which the fuel is made.
B) They are added to the fuel during the refining process.
C) They are formed during the incomplete combustion of the fuel.
D) They are absorbed from the atmosphere while the fuel is stored.
A) They are naturally present in the crude oil from which the fuel is made.
What is the main reason that larger hydrocarbon molecules from crude oil are cracked?
A) To remove impurities like sulfur compounds.
B) To make them less flammable for storage.
C) To break them down into smaller, more useful molecules.
D) To convert them into solid forms.
C) To break them down into smaller, more useful molecules.
Crude oil is formed from the ancient remains of which type of organism?
A) Dinosaurs and land animals.
B) Ancient trees and plants in forests.
C) Plankton buried in mud.
D) Fish living in shallow seas.
C) Plankton buried in mud.
In the process of industrial fractional distillation of crude oil, the hydrocarbons are separated primarily according to which property?
A) Their colour
B) Their density
C) Their flammability
D) Their boiling point
D) Their boiling point
What is the correct general formula for the homologous series of alkanes?
A) CnH2n
B) CnH2n+2
C) CnH2n-2
D) CnHn
B) CnH2n+2
When a hydrocarbon fuel undergoes complete combustion, what are the two main products formed?
A) Carbon and water
B) Carbon monoxide and hydrogen
C) Carbon dioxide and water
D) Carbon and carbon monoxide
C) Carbon dioxide and water
When sulfur compounds present in hydrocarbon fuels are burned, what gas is produced?
A) Sulfur trioxide (SO₃)
B) Sulfur dioxide (SO₂)
C) Hydrogen sulfide (H₂S)
D) Carbon disulfide (CS₂)
B) Sulfur dioxide (SO₂)
Which of the following is a method used for cracking hydrocarbons?
A) Steam cracking
B) Fractional distillation
C) Complete combustion
D) Simple filtration
A) Steam cracking
Crude oil is best described as
A) A single, pure compound.
B) A simple mixture of two or three compounds.
C) A pure element found in liquid form.
D) A mixture of a very large number of compounds.
D) A mixture of a very large number of compounds.
In the tall metal column used for fractional distillation of crude oil, where is the highest temperature found?
A) At the bottom of the column.
B) At the top of the column.
C) In the middle section of the column.
D) The temperature is the same throughout the column.
A) At the bottom of the column.
Which of the following is one of the first four members of the alkane homologous series?
A) Methanol
B) Ethane
C) Ethene
D) Propanol
B) Ethane
What condition is necessary for incomplete combustion of a hydrocarbon fuel to occur?
A) The fuel is heated to a very high temperature.
B) The fuel is in a liquid state.
C) There is an excess supply of air or oxygen.
D) There is a limited supply of air or oxygen.
D) There is a limited supply of air or oxygen.
Oxides of nitrogen are formed in car engines due to:
A) Reactions between hydrocarbons and the engine materials.
B) The high temperatures reached within the engine itself, causing nitrogen and oxygen from the air to react.
C) The presence of catalytic converters in the exhaust system.
D) The incomplete combustion of the fuel.
B) The high temperatures reached within the engine itself, causing nitrogen and oxygen from the air to react.
The products of cracking include alkanes and another type of hydrocarbon. What is the name of this other type of hydrocarbon?
A) Alkynes
B) Alcohols
C) Alkenes
D) Aromatics
C) Alkenes
Most of the compounds found in crude oil are hydrocarbons. What elements make up a hydrocarbon molecule?
A) Hydrogen and oxygen only.
B) Carbon and hydrogen only.
C) Carbon and oxygen only.
D) Carbon, hydrogen, and oxygen.
B) Carbon and hydrogen only.
Why are the properties of hydrocarbons like boiling point, viscosity, and flammability important when considering their use as fuels?
A) They determine if the hydrocarbon is a solid or a liquid at room temperature.
B) They influence how well they burn and how safe they are to use.
C) They tell us how much energy is released when they react with water.
D) They determine the colour and smell of the fuel.
B) They influence how well they burn and how safe they are to use.
Using the general formula CnH2n+2, what is the chemical formula for an alkane molecule that contains 4 carbon atoms?
A) C4H8
B) C4H9
C) C4H10
D) C4H12
C) C4H10
In addition to carbon dioxide and water, which other substances are produced during the incomplete combustion of a hydrocarbon?
A) Both carbon monoxide and carbon (soot).
B) Only carbon monoxide.
C) Only carbon (soot).
D) Only unburned hydrogen.
A) Both carbon monoxide and carbon (soot).
How does sulfur dioxide gas contribute to the formation of acid rain?
A) It reacts directly with nitrogen gas in the atmosphere.
B) It absorbs ultraviolet radiation, cooling the atmosphere.
C) It settles on the ground as solid particles that become acidic.
D) It dissolves in rain water to form acidic solutions.
D) It dissolves in rain water to form acidic solutions.
The products of cracking include alkanes and alkenes. How are alkenes described in relation to alkanes?
A) Alkenes are simply smaller versions of alkanes.
B) Alkenes are saturated hydrocarbons, just like alkanes.
C) Alkenes have the same general formula as alkanes (CnH2n+2).
D) Alkenes are a different type of hydrocarbon compared to alkanes.
D) Alkenes are a different type of hydrocarbon compared to alkanes.
Where is crude oil primarily found?
A) Suspended in the Earth's atmosphere.
B) Dissolved in the water of oceans.
C) Within the Earth's core.
D) Underground within rocks.
D) Underground within rocks.
Generally, hydrocarbon molecules that are larger in size tend to have:
A) Lower boiling points than smaller molecules.
B) Higher flammability than smaller molecules.
C) Higher boiling points than smaller molecules.
D) Lower viscosity than smaller molecules.
C) Higher boiling points than smaller molecules.
Based on the general formula, which of the following chemical formulas represents an alkane?
A) C2H4
B) C3H8
C) C4H6
D) C5H10
B) C3H8
What is the energy change that occurs during the combustion of hydrocarbon fuels?
A) Energy is absorbed from the surroundings.
B) Energy is released into the surroundings.
C) Energy is stored within the products.
D) There is no significant energy change.
B) Energy is released into the surroundings.
Both sulfur dioxide gas, formed from burning sulfur in fuels, and oxides of nitrogen, formed in hot engines, are major contributors to which environmental problem?
A) Global warming
B) Acid rain
C) Ozone layer depletion
D) Smog formation
B) Acid rain
What is the name of the process used to break down larger, less useful hydrocarbon molecules into smaller, more valuable ones?
A) Distillation
B) Cracking
C) Oxidation
D) Refining
B) Cracking