Hydrocarbon Combustion

12 Questions

What is the primary purpose of hazard symbols?

To explain why a substance must be handled carefully

What is the result of incomplete combustion?

Carbon dioxide, water, carbon monoxide, and carbon (soot)

What is the main cause of acid rain?

Sulfur dioxide and nitrogen oxides

What is the primary function of catalytic converters?

To convert carbon monoxide into carbon dioxide

What is the result of the greenhouse effect?

The Earth's surface warms up

What is the best way to control global warming?

Reduce the amount of carbon dioxide released into the air

What is a common characteristic of hydrocarbons?

They are made up of only carbon and hydrogen

What is the purpose of cobalt chloride paper in testing for combustion products?

To detect the presence of water

What is the principle of conservation of mass in reactions?

The mass of the reactants is always the same as the mass of the products

Why should oil fires not be treated with water?

Because water sinks through the oil and causes it to 'spit'

What is the purpose of the fire triangle?

To show the three factors needed for a fire to burn

What is the effect of using a water extinguisher on a fire?

It removes heat from the fire

Study Notes

Hydrocarbons and Combustion

A hydrocarbon is a compound made up of only carbon and hydrogen atoms.
Many fuels are primarily composed of hydrocarbons.
Hydrocarbon combustion reaction: hydrocarbon + oxygen → water + carbon dioxide
Combustion is also an oxidation reaction, as it involves the reaction of a substance with oxygen.

Testing for Products of Combustion

Limewater turns cloudy to indicate the presence of carbon dioxide.
Cobalt chloride paper turns pink to indicate the presence of water.

Conservation of Mass

The law of conservation of mass states that the mass of reactants is equal to the mass of products in a chemical reaction.
Metals can appear to gain mass when heated in air, but this is due to the mass of oxygen that reacts with the metal.
When a hydrocarbon fuel combusts, it appears to lose mass because the products of the reaction (carbon dioxide, water vapor) are lost into the air.

The Fire Triangle and Fire Extinguishers

The fire triangle consists of three essential factors for a fire to burn: fuel, oxygen, and heat.
Removing any one of these factors can extinguish a fire.
Different types of fire extinguishers work in various ways, including:
- Water extinguishers: remove heat
- Powder and carbon dioxide extinguishers: exclude oxygen
- Foam extinguishers: remove heat and exclude oxygen

Hazard Symbols and Air Pollution

Hazard symbols are used to indicate the potential dangers of a substance and the necessary precautions for handling it.
Burning fossil fuels can lead to air pollution, which can harm habitats and organisms.
Incomplete combustion of fossil fuels can produce pollutants such as carbon monoxide, sulfur dioxide, and nitrogen oxides.

Acid Rain and the Greenhouse Effect

Acid rain is formed when sulfur dioxide and nitrogen oxides in the air react with water.
The greenhouse effect is the warming of the Earth's surface due to greenhouse gases such as carbon dioxide in the atmosphere.
Global warming is the predicted result of an increase in the Earth's temperature due to the increased levels of carbon dioxide in the atmosphere, leading to climate change.

Key Vocabulary

Law of conservation of mass: the idea that mass is not lost or gained during a chemical reaction.
Metal: an element that is shiny when polished, conducts heat and electricity well, is malleable and flexible, and often has a high melting point.
Metal oxide: a metal that has combined with oxygen in a chemical reaction.
Non-metal: an element that is not shiny and does not conduct heat and electricity well.
Oxidation: reacting with oxygen.
Oxide: a compound that contains oxygen, often formed through the reaction of a metal with oxygen.