Module 3 Flashcards
Explain the test for hydrogen.
Hydrogen gas burns with a squeaky pop
Explain the combustion of hydrogen.
Hydrogen reacts with oxygen in the air to form water.
Why is hydrogen the fuel of the future?
1.Using renewable energy, water molecules can be split using electrolysis to produce hydrogen and oxygen
2.The hydrogen reacts with oxygen to release energy (exothermic reaction)
3. The only product of combustion is water.
Name the 3 fossil fuels
Coal, oil and natural gas
How is coal formed?
Millions of years ago giant plants died. Over the next million of years these plants were buried under water and dirt. HEAT and PRESSURE turned these dead plants into COAL.
How were oil and natural gas formed?
Plankton died and were buried in the ocean floor and over time they were covered by layers of silt and sand. Over millions of years the remains turned to oil and gas due to enormous HEAT and PRESSURE. Today we drill though the layers of silt, sand and rock to reach rock formations containing oil and gas.
What happens to fossil fuels in the air?
They undergo combustion with oxygen
What are the products of combustion?
Carbon dioxide and water
What are hydrocarbons?
Molecules that consist of carbon and hydrogen only.
What does crude oil contain?
A mixture of hydrocarbons.
What is Fractional Distallation?
The process used to separate crude oil into different fractions.
Give the definition for ‘fraction’
A group of compounds with boiling points within a given range.
Uses of fractions…
Refinery gas
Petrol
Naptha
Kerosene
Diesel
Lubricating oil
Fuel oil
Residue
Give the definition for ‘ boiling point’
The temperature at which a liquid turns into a gas.
Give the definition for ‘ flammability’
Ease of combustion
Give the definition for ‘ viscosity ‘
A description of how thick a liquid is
Give the definition for ‘ volatility ‘
Ease of evaporation.
Why do fractions have different properties?
They contain hydrocarbons of different sizes
What does the size of a hydrocarbon depend on?
The number of carbon atoms it has
What will happen to the boiling point, the flammability, and the viscosity as the number of carbon atoms increase?
The boiling point will increase
The flammability will decrease
The viscosity will increase
Describe fractions containing small hydrocarbons
Volatile
Light and colour
Runny
Highly flammable
Describe fractions containing large hydrocarbons
Darker in colour
Viscous
Not so flammable
Not volatile
What are the two major issues associated with burning fossil fuels?
Global warming and acid rain.
What happens when there is an increase in the amount of carbon dioxide in the atmosphere?
Traps re-radiated heat
Less heat is emitted to space
Global temperatures rise and climate change occurs
Describe incomplete combustion
In a limited supply of oxygen fossil fuels (hydrocarbons) burn to produce carbon, carbon monoxide and water
Give the equation for incomplete combustion
Hydrocarbon + oxygen —-> carbon + carbon monoxide + water
What is sulphur?
An impurity found in coal
How is sulphur dioxide made?
When Cole is burned in power stations, the sulphur combines with oxygen to produce sulphur dioxide
Give the word equation for sulphur dioxide
sulphur(s) + oxygen(g) —> sulphur dioxide(g)
How is nitrogen dioxide produced?
It is produced by the sparking of air in car engines.
Give the word equation for nitrogen dioxide.
Nitrogen(g) + oxygen(g) —> nitrogen dioxide(g)
When nitrogen dioxide is dissolved in rain water what is formed?
An acidic solution.
Describe Negative impacts of acid rain.
- Damages buildings made from limestone and marble.
- Accelerates the corrosion of metal structures
- Kills plant life
- Harmful to aquatic organisms
