Can somebody please please please help me in this rock hard question
http://www.thestudentroom.co.uk/showthread.php?t=2365732

I'm so unsure with ionic equations :frown:

(edited 10 years ago)

Reply 185

Welbeck

don't you think there is a LOT to remember in this exam like at the stuff about the halogens, atmosphere and reactions

Reply 186

krisshP

Original post by Welbeck

don't you think there is a LOT to remember in this exam like at the stuff about the halogens, atmosphere and reactions

I agree, F332 is LOADED with so much content!

Reply 187

Jlane5000

Hi can someone please help me with this part of the spec "Explain the risks associated with the storage and transport of the halogens (fluorine to iodine)"

I've gone through all past paper mark schemes and can't compile a complete list. I know they are toxic/corrosive and that they should all be kept away from flames, but are there any specific ones for each halogen?

Cheers :biggrin:

Reply 188

Aaaaa11111

Are there any trends or patterns shown throughout the past papers? And does anyone have an sample questions for the pre-release? Thanks

Reply 189

krisshP

Original post by Aaaaa11111

Are there any trends or patterns shown throughout the past papers? And does anyone have an sample questions for the pre-release? Thanks

Flick through the previous pages in this thread and you'll find them :smile:

Reply 190

super121

Original post by krisshP

Can somebody please please please help me in this rock hard question
http://www.thestudentroom.co.uk/showthread.php?t=2365732

I'm so unsure with ionic equations :frown:

From the equation in the advanced notice, you can see that Na is a spectator ion, so just get rid of it. Then, split the reactants into ions (you know what chlorine in sodium chlorate had an oxidation state of 5 so it will be 2ClO3-). The same products form (minus sodium chloride), so all thats left to do is balance it. :smile:

Reply 191

krisshP

Original post by super121

Why is Na a spectator ion, is it because its oxidation state does not change?

Reply 192

krisshP

Original post by super121

How come you split reactants into ions, but nor products? Btw what are ionic equations supposed to show us and how do they help us?

Thanks! :biggrin:

Reply 193

krisshP

Why did you minus sodium chloride?

Reply 194

super121

Original post by krisshP

How come you split reactants into ions, but nor products? Btw what are ionic equations supposed to show us and how do they help us?

Thanks! :biggrin:

They show us what is oxidised and what is reduced.
Well, if we know how to use them, they help us by enabling us to pass the exam? :P

Original post by krisshP

Why did you minus sodium chloride?

Because they Sodium is not involved in the reaction (Sorry, I'm really bad at explaining things)

Reply 195

krisshP

Original post by super121

They show us what is oxidised and what is reduced.
Well, if we know how to use them, they help us by enabling us to pass the exam? :P

Because they Sodium is not involved in the reaction (Sorry, I'm really bad at explaining things)

Pass the exam hahahaha lol :biggrin:

Let's hope they don't give a scary question like this in the exam.

If sodium is a spectator ion, why did you get rid of the chlorines that are ended up being with Na?

Reply 196

super121

Original post by krisshP

Pass the exam hahahaha lol :biggrin:

Let's hope they don't give a scary question like this in the exam.

If sodium is a spectator ion, why did you get rid of the chlorines that are ended up being with Na?

You're not really getting rid of it because it balances with the other chlorines.

Reply 197

krisshP

Original post by super121

You're not really getting rid of it because it balances with the other chlorines.

So with ionic equations the reactants are expressed as ions if they are aqueous and the products are never expressed as ions? The spectator ions are ions which have had no change in oxidation state and are not displayed in the ionic equations right?

Thanks

Reply 198

Welbeck

for nucleiphilic substitution, has someone got good way of explaining it to me when it is an a nuclepohile molecule cuch as h20. The main part I don't get is where the + comes from on the O (page 292 CI)