Hydrocarbons Flashcards
(29 cards)
What is crude oil?
A non-renewable mixture of different compounds, primarily hydrocarbons, found in rocks and fossils.
What are hydrocarbons?
Molecules made up of only hydrogen and carbon atoms.
What are the properties of crude oil?
A mixture of compounds that are not chemically combined, mainly hydrocarbons.
What are heavy fractions in crude oil?
Do not make good fuels, do not ignite easily, have high boiling points, and low volatility.
What makes a good fuel?
Ignites easily, low boiling point, low emissions, high volatility, and cheap.
What is the general formula for alcohols?
C_nH_{2n+1}OH.
What is the formula for alkanes?
C_nH_{2n+2}.
What characterizes saturated hydrocarbons?
Only contain single bonds.
What is phosphoric acid?
A strong acid commonly used as a catalyst for alkenes.
What are the types of alkanes?
- Methane (CH4)
- Ethane (C2H6)
- Propane (C3H8)
- Butane (C4H10)
What are the properties of short chain hydrocarbons?
Highly volatile, ignite easily, and have low boiling points.
How do hydrocarbons’ boiling points change with chain length?
Hydrocarbons with longer chains have higher boiling points and require more energy to break bonds.
What happens when hydrocarbons are burned with enough oxygen?
Energy is released, producing carbon dioxide and water.
True or False: Longer chain hydrocarbons are more flammable.
False.
What is the significance of viscosity in hydrocarbons?
Hydrocarbons with longer chains have higher viscosity, making them thicker and less flowy.
What is carbon monoxide?
A colourless, odourless, toxic gas
It is formed during the incomplete burning of carbon-containing substances.
What is the purpose of fractional distillation?
Separating crude oils into groups of hydrocarbons with similar amounts of carbon atoms
This process helps in the production of fuels and feedstock.
What are long chain hydrocarbons?
Hydrocarbons with many carbon atoms
They have higher boiling points and condense at the bottom of the fractional distillation column.
What are short chain hydrocarbons?
Hydrocarbons with few carbon atoms
They have lower boiling points and condense at higher temperatures near the top of the fractional distillation column.
What happens to hydrocarbons during fractional distillation?
They are separated based on different boiling points
This allows for the collection of various fractions as liquids.
Define homologous series.
A group of organic compounds with the same functional group but different numbers of hydrogen and carbon atoms
Examples include alkanes, alkenes, alcohols, and carboxylic acids.
What is cracking in the context of hydrocarbons?
The process of breaking longer chained hydrocarbons into shorter chained hydrocarbons
This makes the shorter chains more useful for various applications.
What type of reaction is cracking?
A thermal decomposition reaction
It produces alkenes and alkanes as products.
What is steam cracking?
A method where vapourised hydrocarbons are mixed with steam in a high temperature environment
This process yields alkenes and alkanes.
