Combustion Flashcards
Generalised definition of Combustion
Combustion is a Rapid Oxidation, exothermic reaction between Oxygen and a Fuel (Usually a hydrocarbon (a substance containing only C and H)) to produce an Oxide and energy. It is usually fast and creates heat and light. The products are — which are products of in/complete combustion
Definition of Incomplete Combustion
Incomplete Combustion Occurs when their is a limited supply of air/oxygen gas and produces less heat and light than Complete Combustion. It is also less efficiant as it produces less energy. The products of Complete combustion are Carbon Monoxide, Soot(Unburnt Carbon), and Water Vapour.
Definition of Complete Combustion
Complete Combustion Occurs when there is an plentiful supply of Oxygen and produces lots of heat and light. The products of Complete Combustion are Carbon Dioxide and Water Vapour.
Describe the impact of complete combustion products on human health and the enviroment
Human Health: As complete combustion produces carbon dioxide which is a greenhouse gas, it leads to poor air quality which can be detrimental to human health.
Enviroment: The products of complete combustion are linked to changing concerntrations of carbon dioxide in the atmosphere, as it literally produce carbon dioxide (which is a greenhouse gas) and leads to climate change.
Describe the impact of incomplete combustion products on human health
Human Health: Carbon Monoxide binds very tightly to the haemoglobin in the same place as Oxygen does which barriers Oxygen from being transported to all blood cells, affectively starving the body of Oxygen as it can no longer be carried. Exposure to high concerntrations of carbon Monoxide over a long period of time can cause the human to experience a coma, collapse, loose conciousness, or even death.
Enviroment: Carbon Monoxide products can pollute the air.
Identify reactions as either complete or incomplete combustion
1. 4CH₄ + 5O ₂ → 8H₂O+ 2CO + 2C
2. C₃H₈ + O₂ → CO + H₂O
3. C₄H₁₀ + O₂ → CO + H₂O
4. C₃H₈ + 5O₂ → 3CO₂ + 4H₂O
5. C₄H₁₀ + 6.5O₂ → 4CO₂ + 5H₂O
6. CH₄+2O₂→CO₂+2H₂O
7. C₃H₈+5O₂→3CO₂+4H₂O
8. C₅H₁₂ + O₂ → CO + H₂O
9. C₆H₁₄ + O₂ → CO + H₂O
10. C₅H₁₂ + 8O₂ → 5CO₂ + 6H₂O
- Incomplete
- Incomplete
- Incomplete
- Complete
- Complete
- Complete
- Complete
- Incomplete
- Incomplete
- Complete
what is the concept of hydrocarbons and their combustion products
Hydrocarbons are compounds containing only Carbon and Hydrogen atoms such as fossil fuels(coal, oil, and natural gas). When Hydrocarbons combust (burn in the presence of oxygen) they form carbon dioxide and water.
Provide examples of combustion reactions
An example of combustion is a stove top when the gas(a fuel) reacts with oxygen to spark a flame. Soot is produced and is deposited on the bottom of a pot or pan being heated.
Balance chemical equations for complete and incomplete reactions
1. C₄H₁₀ + O₂ → CO + H₂O
2. C₆H₁₄ + O₂ → CO₂ + H₂O
3. C₇H₁₆ + O₂ → CO + H₂O
4. C₈H₁₈ + O₂ → CO + H₂O
5. C₉H₂₀ + O₂ → CO + H₂O
6. C₁₀H₂₂ + O₂ → CO + H₂O
7. C₇H₁₆ + 11O₂ → 7CO₂ + 8H₂O
8. C₈H₁₈ + 12.5O₂ → 8CO₂ + 9H₂O
9. C₉H₂₀ + 13O₂ → 9CO₂ + 10H₂O
10. C₁₀H₂₂ + 14O₂ → 10CO₂ + 11H₂O
The balanced versions for the given equations are:
- 2C₄H₁₀ + 13O₂ → 8CO + 10H₂O
- 2C₆H₁₄ + 19O₂ → 12CO₂ + 14H₂O
- 2C₇H₁₆ + 21O₂ → 14CO + 16H₂O
- 2C₈H₁₈ + 25O₂ → 16CO + 18H₂O
- 2C₉H₂₀ + 23O₂ → 18CO + 20H₂O
- 2C₁₀H₂₂ + 28O₂ → 20CO + 22H₂O
- 2C₇H₁₆ + 23O₂ → 14CO₂ + 16H₂O
- 2C₈H₁₈ + 25O₂ → 16CO₂ + 18H₂O
- 2C₉H₂₀ + 29O₂ → 18CO₂ + 20H₂O
- 2C₁₀H₂₂ + 31O₂ → 20CO₂ + 22H₂O
Observe combustion reactions and discuss trends
CO2 (Carbon Dioxide) Is/n’t present because limewater turns cludy if CO2 is detected but otherwise remains transparent if CO (Carbon Monoxide) is present
H2O (Water Vapour) Is
present because if Blue colbalt chloride paper turns pink if moisture is detected but otherwise remains blue
Unburnt Carbon (soot) is present if there is limited Oxygen avalible so not all of the C atoms from the Fuel have enough oxygen to form carbon dioxide so some form CO or remains unreacted as Carbon (Soot) which is a light black powder often stuck to the bottom of a beaker as a product of incomplete combustion.
What is the role of Oxygen in Combustion?
It determines whether combustion will be complete of incomplete which changes the products formed from the reaction. If there is a lack of Oxygen then incomplete combustion will occur and vice versa.
How is mass Conserved in Combustion?
A balanced equation shows that mass is conserved because the number and type of atoms in both the reactants and products are the same since mass cannot be gained ot lost by itself, the atoms determine the mass and no atoms have been introduced or lost in the reaction. All atoms/elements/ ions in the products can be traced back to the reactants. The total mass of (carbon/), carbon monoxide/dioxide and water will be equal to the total mass of ethanol and oxygen. The reactants and products both have the same number of each type of element
i.e…
