Shortly, hydrocarbons are organic compounds containing carbon and hydrogen.
It is cars
The water cycle is the system that go around and over over again.
It is when you break large hydrocarbons/alkanes, into smaller more useful alkanes/alkenes. For example a large hydrocarbon in crude oil is Bitumen. By passing this substance over a hot catalyst, you can break it down into smaller hydrocarbons such as Petrol or Diesel
The ozone layer is very thin.
The process is called 'cracking' or more properly "Fluid Catalytic Cracking". It takes place in a Catalytic Cracker (cat cracker) where a combination of high heat, pressure, and chemical catalysts break long chain hydrocarbons into more valuable shorter chain ones. A catalyst is a compound that speeds up (or slows down) a reaction without being used in the reaction. So a catalyst can be used over and over again for the same process.
Some of the physical properties of hydrocarbons include the fact that hydrocarbons are non-reactive and are soluble in water. Hydrocarbons are able to burn over a flame and will produce water and carbon dioxide when reacting with oxygen. Most hydrocarbons are less dense than water and are able to float on water. Hydrocarbons are non-polar and will react with bromine and potassium under certain circumstances.
It is cars
Summarize what you said in the earlier paragraphs and you will have your conclusion.
Over all feedback
They use hydrocarbons now; they used to use chlorofluorocarbons (CFC's) which were damaging to the ozone layer.
Conclusion? There hasn't been any conclusion. The Church of Jesus Christ of Latter-day Saints (the 'Mormon' church) is still going strong and has reported significant growth every year since it began over 180 years ago. Today there are over 14 million Mormons all over the world. The idea of a 'conclusion' for Mormons is an interesting one. Some Mormons might say that the conclusion will be the Second Coming of Jesus Christ, while others would argue that there is no conclusion because life is eternal. Either way, Mormons believe that their faith will never be removed from the earth, so there will never be a conclusion of Mormonism.
The water cycle is the system that go around and over over again.
It is when you break large hydrocarbons/alkanes, into smaller more useful alkanes/alkenes. For example a large hydrocarbon in crude oil is Bitumen. By passing this substance over a hot catalyst, you can break it down into smaller hydrocarbons such as Petrol or Diesel
you can't......you have to start all over.
that worms will take over the earth that worms will take over the earth
Your conclusion must depend on what you have written in your essay. We can't write it for you. Read over what you've already written and summarize that in one or two sentences. The conclusion is a brief summary of what the whole essay is saying.
The ozone layer is very thin.