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Chemistry :)
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| 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 |