MCQ corrections Flashcards
How do we recognise it’s a neutralisation reaction?
Make sure it’s an acid and a base ( eg. Can rule out if it’s a metal and acid )
Make sure the base accepts a H+ ion
What is the shape of graphene?
Same as graphite, trigonal planar
How do you recognise which has the biggest FIRST ionisation energy?
Use ionisation energy trends - look across the period and see which ones is furthest to the right and up
How do you recognise sturcture isomers?
Same molecular formula, different structural formula
Count the number of carbons ( and H if needed ) ans find molecular formula
How to count sigma and pi bonds
All single bonds are sigma bonds
Double bonds have pi AND sigma bonds ( one double bond = 1 sigma and 1 pi )
How to recognise if something has non polar molecules ( with E Z isomers )
Z isomers automatically cannot be because dipoles are on the same side
Dipoles are opposite each other they CANCEL OUT
Which element has a very high melting point?
Carbon
Why does nitrogen have a higher IE than oxygen?
O = 2p4 repulsion so lower activation energy
Less energy required to remove the electrons
What does 0.200 mol do -3 of na2co3 mean in terms of the conc of Na+?
There is 0.400 moles
How would you find the Reagant needed to neutralise?
Look at the number of H+ ions by looking at the number of atoms
Then make sure the H+ ions is the same and can NEUTRALISE this ( neutralisation is to do with H+ ions )
What are the conditions for hydrogen bonding?
The hydrogen has to be DIRECTLY BONDED to N, O, F
Titration q
You can wash out the conical flask, but not the pipette as used for the other solution. It can dilute the other solution so a larger titre will be needed. If water overfills the volumetric flask, solution is too dilute and therefore a larger titre is needed.
