Erstellt von Mel Hughes
vor mehr als 8 Jahre
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Why do ionic solids have high melting points?
Why can ionic substances conduct electricity when molten or when dissolved in water?
Why does petrol not conduct electricity?
Why are substances with large molecules more likely to be liquids or solids at room temperatures?
Why do substances with giant covalent structures have very high melting points?
Give 2 similarities between diamond and graphite
Give 2 differences between diamond and graphite
Give 2 similarities between graphite and fullerenes
Give 2 differences between graphite and fullerenes
Why can metals be made into wires?
Give two reasons why alloys can be more useful than pure metals
Why are metals good conductors of electricity?
Why do LD and HD poly(ethene) have different properties?
What is the main difference in the structures of thermosoftening and thermosetting polymers?
What allows thermosetting polymers to be remoulded?
What is a nanoparticle?
Scientists have developed a new deodorant containing nanoparticles. What should be done before it is sold for people to use?
Why does it take a lot of energy to melt sodium chloride?
Why are compounds like methane, CH4 and ammonia, NH3, gases at room temperature?
Polymers made from different monomers have different properties. Explain why
Some dental braces are made from shape-memory alloys. What is meant by a 'shape-memory alloy'?
Explain why diamonds are very hard
Why do ionic compounds need to be molten or in solution to conduct electricity?
Explain why a block of copper can be hammered into a sheet
Silver nanoparticles are used in some socks to help prevent bad smells
How are silver nanoparticles different from ordinary silver particles?
Suggest why a sock manufacturer would use nanoparticles instead of ordinary silver particles
Explain why thermosetting polymers are often used to make handles for cooking pans
Explain how the atoms in a metal are bonded to each other
Why can graphite conduct electricity?
Explain what is meant by 'intermolecular forces'
C60 is a fullerene. What are fullerenes?