The Standard Grade Chemistry Thread!

Original post by -Neuro-

What did people put down for the reaction which caused the breakdown of starch?

Hydrolysis :banghead:

Reply 181

Silverngold

Original post by nerd434

It is Hydrolysis is it not?

Hydrolysis maybe?

Reply 182

Original post by nerd434

It is Hydrolysis is it not?

I had serious doubts about it , not sure..

Reply 183

Original post by -Neuro-

I thought it was the particle size of the zinc. Experiment 2 had a slower rate of reaction, thus had a zinc particles which were larger.

I wrote a story afterwards giving an explanation(although you didn't need to, I only did ot because I had loads of time left after).

What did you put? :smile:

I put the concentration of the acid :s

Reply 184

Original post by Silverngold

Did anyone get 45% for the aluminium or 44.89...?

yes that's what I got :smile:

Reply 185

kierandoran

Original post by Aay

I had serious doubts about it , not sure..

Yes it was hydrolysis

Reply 186

kierandoran

Original post by iloveparis

I put the concentration of the acid :s

It couldn't have been, it said in the question that for both experiments 1 mol/l HCl was used unfortunately

Reply 187

What did people get for the number of mols of aluminium, think it was the last question of the paper? I got 0.93 mol

Reply 188

Original post by kierandoran

Yes it was hydrolysis

haha phew,

You guys remember any other questions ?

Reply 189

eilidhb

Original post by Silverngold

Something like AlSO4

Think I did that question wrong then :/

Reply 190

Original post by kierandoran

It couldn't have been, it said in the question that for both experiments 1 mol/l HCl was used unfortunately

aw damn

Reply 191

Original post by nerd434

It definitely is, I checked all the reaction definitions in the textbook. Hydrolysis is to break a bigger molecule (starch) into smaller molecules (glucose normally) through the insertion of water. It's because starch it too big to fit through the gut wall.

Read answer 2/3: http://answers.yahoo.com/question/index?qid=20080812084415AAERUDf

Thats great man,

thanks for clearing it up !

Reply 192

sherbet_lemons7

19

Original post by nerd434

It definitely is, I checked all the reaction definitions in the textbook. Hydrolysis is to break a bigger molecule (starch) into smaller molecules (glucose normally) through the insertion of water. It's because starch it too big to fit through the gut wall.

Read answer 2/3: http://answers.yahoo.com/question/index?qid=20080812084415AAERUDf

I can second this. It's definitely hydrolysis- it's part of the biology course. :smile:

Reply 193

-Neuro-

Original post by nerd434

Yeah I got like 44.84% then rounded it to 45%.

I just said something about the mass of Zinc being used may have been different.

And for the Chlorine question, I'm pretty sure it was oxidation.

I got that for the calculation and I think I put oxidation.

But the mass doesn't affect the rate of reaction, it affects the quantity of product produced but not the rate.

Original post by kierandoran

Yes it was hydrolysis

HUZZAH! Got hydrolysis.

For the what bond is broken between sodium and chloride.

Was the answer just ionic bond?

(edited 10 years ago)

Reply 194

Im trying to remember some of the questions that came up to run through what i got but cant remember anything ! :angry:

Reply 195

Original post by -Neuro-

I got that for the calculation and I think I put oxidation.

But the mass doesn't affect the rate of reaction, it affects the quantity of product produced but not the rate.

BAZINGA! Got hydrolysis.

For the what bond is broken between sodium and chloride.

Was the answer just ionic bond?

I wrote ionic..

Reply 196