Question | Answer |
Why is the first ionisation energy of potassium less than sodium? | The bigger atom is further away from the nucleus.
The inner electrons shield the outer electrons from the attraction of the nucleus |
What is a feedstock? | The reactant from which other chemicals can be made |
Why does a small increase in temperature produce a large increase in reaction rate? | More molecules have energy greater than the activation energy |
What colour change would be seen by dichromate solution? | Orange to green |
In terms of intermolecular bonding present, why does ammonia have a relatively high boiling point? | There are strong hydrogen bonds between the molecules and there is a big difference in electronegativity between nitrogen and hydrogen which makes covalent bonds very polar |
Why does the first ionisation energy decrease going down groups? | The outer electron is further away from the nucleus and there is increased shielding by the inner electrons |
How are ethene and propene made from the naptha fraction? | Cracking |
Kevlar is formed from what kind of polymeridsation? | Condensation |
What polymer can dissolve in water? | Polyethenol |
What structure do polyester fibres have? | Linear |
What structure do polyester resins have? | Cross linked |
Synthesis Gas? | Carbon monoxide and hydrogen |
Which oxide forms an aqueous solution with ph greater than7? | Sodium oxide |
What are the two hydrogen atoms in a molecule of hydrogen held together by? | Non polar covalent bond |
What is stronger - covalent or hydrogen? | Covalent |
What type of bonding and structure is found in a fullerene? | Covalent molecular |
What kind of moleculaes is carbon tetrachloride made up of? | Non-polar molecules |