AQA gcse chemistry units 2+3 14th may

Reply 20

Synonym

16

All i know is that C3 is going to be a hard exam :/ i am so not prepared for this c3 exam FFFFS

Reply 21

SmashedIt

5

So basically, acids are substances that produce H+ ions when reacted with water. an acid reacted with a metal makes a salt and hydrogen. An acid reacted with a base makes a salt and water. These reactions can be used to make salts. After the reaction the mixture is filtered leaving a solution of the salt which can be collected by evapourating the solution. Hope it helps

Reply 22

ell57

1

Can anyone explain what a lattice is?

Reply 23

SmashedIt

5

When you make insoluble salts the precipitate formed can be filtered and then washed with distilled water and dried

Reply 24

Dannbutlerr

I have heard by a few videos and teacher the predicted 6 marker on unit 3 is the method for titration

Reply 25

username1547241

12

Original post by warty_toe

The Harber process is where Nitrogen form the Air is reacted with Hydrogen found as natural gas, to form Ammonia. The reaction commonly takes place at 200 Atmospheres (pressure), 450'C and in the presence of an Iron Catalylst. The ammonia is condensed once reacted to stop it from escaping as a gas.

thank you!!

Reply 26

SmashedIt

5

Lattice is just like a cubic structure of atoms/particles. Ionic lattices contain two types of atoms, positive and negative which have attraction in all direction. Metallic latices are just metal atoms which are arranged in layrs and has delocalised electrons, so the meta are ions not atoms

Reply 27

ell57

1

Original post by SmashedIt

Lattice is just like a cubic structure of atoms/particles. Ionic lattices contain two types of atoms, positive and negative which have attraction in all direction. Metallic latices are just metal atoms which are arranged in layrs and has delocalised electrons, so the meta are ions not atoms

thanks so can a lattice can be made up from ionic and covalent bonds??

Reply 28

SmashedIt

5

Original post by ell57

thanks so can a lattice can be made up from ionic and covalent bonds??

I think so but i think lattices are not only cubic, diamond is a covalent lattice i believe

Reply 29

neon_reaper

7

Original post by SmashedIt

I think so but i think lattices are not only cubic, diamond is a covalent lattice i believe

A lattice is just a large repeated structure: metals are lattices as well

Reply 30

jamestg

21

Original post by jamestg

Sh*ting myself right now. But I'll post what I'm feeling after revision/past papers tonight...

Did some refreshing of content and past papers. Didn't do too well on the past papers - 2 As and 1 low A*...

Getting up at 6am to revise for an extra hour, listening to BBC bitesize audio things on the way to school - hopefully this combined with easy questions will mean I can get an A*!

I'm so nervous still, I don't think I'll sleep much.

Reply 31

zaby786

4

Does anyone know how i can plan my revision because it's tomorrow and i don't know what to do!!! :frown:

Reply 32

LuLu<3

2

Found C3 SO much better than C2 although the lack of titration calculations and bond energies was disappointing, can imagine C3 grade boundaries to be VERY high. How did everyone else find it?

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Reply 33

isabellagrace

2

[QUOTE=LuLu it was so annoying :( but at that it was fine apart from the volatile question hahahha

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Reply 34

emmaalouisee

12

Original post by LuLu<3

Found C3 SO much better than C2 although the lack of titration calculations and bond energies was disappointing, can imagine C3 grade boundaries to be VERY high. How did everyone else find it?

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I honestly though C2 was really easy compared to C3, I struggled a lot with C3!