Chemistry Test of Ions

[wooowooowoo]

sorry i was wondering whether u made this list of camridge did.....im confused u said that here is a list i made but later u said official from CIE

The attachment is composed by me and then later I found that even the syllabus consists of a list; hence the photo.

 

[ThatReallyReallyWeirdDude]

sorry i was wondering whether u made this list of camridge did.....im confused u said that here is a list i made but later u said official from CIE

That list is directly from the cambridge syllabus, which can be found on this website.

 

[Sajal mehta]

The attachment is composed by me and then later I found that even the syllabus consists of a list; hence the photo.

oh cool....thanks....and oh...my teachers gave me a IB tests list shud i remember that or this?

 

[wooowooowoo]

oh cool....thanks....and oh...my teachers gave me a IB tests list shud i remember that or this?

The syllabus one is just fine, they won't ask something which is not coming in the exam.

 

[Sajal mehta]

The syllabus one is just fine, they won't ask something which is not coming in the exam.

will do thanks....do u have ur exam 2moro?...or have u finished igcse?

 

[wooowooowoo]

will do thanks....do u have ur exam 2moro?...or have u finished igcse?

Haha no, I'm writing tomorrow as well

 

[ZainH]

Sure. I love questions
I'll be waiting

Q2)c) http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Chemistry (0620)/0620_s03_qp_6.pdf

And why? :S

 

[wooowooowoo]

Q2)c) http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Chemistry (0620)/0620_s03_qp_6.pdf

And why? :S

As you can see it says

50 cm3 of sodium thiosulphate solution was poured into a
100 cm3 beaker. The beaker was placed on a cross drawn on a piece of paper. 10 cm3 of
hydrochloric acid was added to the beaker and the timer started.

That means Acid is being added onto the Sodium Thiosulphate

So that means Sodium Thiosulphate is first
To make it a fair test, the volume of liquid is kept constant so the volume kept constant here is Sodium Thiosulphate and water (Both should add up to 50 cm3)
So we add water second to make volume equal
Finally add the acid for the reaction to take place

 

[ThatReallyReallyWeirdDude]

Q2)c) http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Chemistry (0620)/0620_s03_qp_6.pdf

And why? :S

Hmm
Answer is Sodium Thiosulphate/Water/Hydrochloric acid or Water/Sodium Thiosulphate/Hydrochloric acid
The actual experimental procedure in the question says it adds the hydrochloric acid TO the sodium thiosulphate, so that should basically tell you that water or sodium thiosulphate is first.
I'm not sure honestly.
I think it's a combination of a) The sodium thiosulphate/water is in excess and b)If you added the sodium thiosulphate to the hydrochloric acid it would form the colour before all the volume is there.

 

[wooowooowoo]

I'm not sure honestly.
I think it's a combination of a) The sodium thiosulphate/water is in excess and b)If you added the sodium thiosulphate to the hydrochloric acid it would form the colour before all the volume is there.

It's always the acid being added to the base. No idea why but it's always like that :|

 

[ZainH]

As you can see it says

That means Acid is being added onto the Sodium Thiosulphate

So that means Sodium Thiosulphate is first
To make it a fair test, the volume of liquid is kept constant so the volume kept constant here is Sodium Thiosulphate and water (Both should add up to 50 cm3)
So we add water second to make volume equal
Finally add the acid for the reaction to take place

Thanks, expect a few more.. solving past papers atm.

 

[ZainH]

As you can see it says

That means Acid is being added onto the Sodium Thiosulphate

So that means Sodium Thiosulphate is first
To make it a fair test, the volume of liquid is kept constant so the volume kept constant here is Sodium Thiosulphate and water (Both should add up to 50 cm3)
So we add water second to make volume equal
Finally add the acid for the reaction to take place

All right same paper, question 3. It says a burette was filled up to the 0.0cm3 mark with solution A of sodium thiosulphate. Then in part a)i) it says in which experiment was the greatest volume of aqueous sodium thiosulphate used? I said experiment 2 since, in experiment 1 there was barley any.. (o.ocm3 mark) .. answer is experiment 1.. How? :S

As you can see, I'm terrible at chemistry..

 

[wooowooowoo]

All right same paper, question 3. It says a burette was filled up to the 0.0cm3 mark with solution A of sodium thiosulphate. Then in part a)i) it says in which experiment was the greatest volume of aqueous sodium thiosulphate used? I said experiment 2 since, in experiment 1 there was barley any.. (o.ocm3 mark) .. answer is experiment 1.. How? :S

As you can see, I'm terrible at chemistry..

The difference in experiment 1 is more than that of experiment 2 hence experiemnt 1 used greater volume of thiosulphate
nah don't say that! We all are here to help you out

 

[ZainH]

The difference in experiment 1 is more than that of experiment 2 hence experiemnt 1 used greater volume of thiosulphate
nah don't say that! We all are here to help you out

But what does the difference have to do with the volume of sodium thiosulphate? Since in the question they said it was only filled up to the 0.0cm3 mark :S

 

[wooowooowoo]

But what does the difference have to do with the volume of sodium thiosulphate? Since in the question they said it was only filled up to the 0.0cm3 mark :S

It was filled till 0.0 cm3 mark means the whole burette was filled and the liquid was dropped until the reaction was over.
In the first experiment more liquid was used up hence more Thio used up

 

[ZainH]

It was filled till 0.0 cm3 mark means the whole burette was filled and the liquid was dropped until the reaction was over.
In the first experiment more liquid was used up hence more Thio used up

Ah, all right thanks , noowww I understand x)

 

[thats_me]

Thanks a lot both of you!

anothr doubt
in O/N 4 Q4d it's asked that how temp changes would differ if more volume(40cm3) of water is used? :S the ans is small temp changes :/ y?
anddd in some ques it's asked if the reaction is 1:1 then which reactant has a higher conc? is it the one that has the higher volume or the one that has lower

 

[wooowooowoo]

anothr doubt
in O/N 4 Q4d it's asked that how temp changes would differ if more volume(40cm3) of water is used? :S the ans is small temp changes :/ y?
anddd in some ques it's asked if the reaction is 1:1 then which reactant has a higher conc? is it the one that has the higher volume or the one that has lower

As more water is present, it will have more things to react with so the temp will increase slowly compared to previous one. You see if you have to eat one piece of cake it'll take 5 minutes but when you have to eat 2, it'll take 10.

And I don't get the second question, which past paper?

 

[Sajal mehta]

Q6)b) http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Chemistry (0620)/0620_w11_qp_62.pdf
plz help

 

[thats_me]

As more water is present, it will have more things to react with so the temp will increase slowly compared to previous one. You see if you have to eat one piece of cake it'll take 5 minutes but when you have to eat 2, it'll take 10.

And I don't get the second question, which past paper?

lol cake thing it depends on hw hungry i am but yea got it thanks.. ummmm i don rem the year it was like potassium chloride was being made and the reactants were hcl & koh ,,, hcl was 19cm3 & koh was 25cm3 i guess ,n the ques was which is more concentrated? sooo yea which one?