Chemistry 5 Cracking Hydrocarbons GCSE Core

Question	Answer
Give three reasons why fractions from crude oil are cracked	Contains too many large hydrocarbons --- Do not flow easy --- Difficult to ignite
What does cracking produce?	Alkane's and Alkene's
Are Alkenes saturated or unsaturated	Unsaturated
What Colour does Alkenes turn bromine water	From Orange to Colourless
Give two ways how hydrocarbon molecules be cracked	Heating them with steam to a very high temperature --- Passing their vapours over a hot catalyst
What is a polymer?	Plastics are large molecules made when many small molecules join together
What makes Polymers?	Monomers
What are plastics made of	Polymers
What can alkenes be used to make?	Polymers such as poly(ethene) and poly(propene)
Describe one use of a smart polymer	A shape memory Stitch
How does a Shape memory stitch work?	It uses the temperature of the body to make the threat tighten and close the wound
What does 'Biodegradeable' mean?	A substance or object capable of being decomposed by bacteria or other living organisms and thereby avoiding pollution
3 ways of reducing plastic waste	Reuse Bags and bottles --- Make more Biodegradeable products --- Use recycling bins
Outline the two ways that can be used to make ethanol and give an advantage and a disadvantage of each method.	Fermenting sugar using enzymes in yeast = Sustainable only uses plant material ➝➝➝ Hydration of ethene with steam in the presence of a catalyst = Unsustainable needs crude oil

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	Created by Chloe Roberts over 10 years ago