Chemistry doubts..ask here!

[narutogirl]

well, when i did the bio i really benefited from all the questions asked and the answers given
so i thought we could do the same for chemistry..for me chemistry is one of loveliest papers ( ya i know loveliest sounds weird, but its the only word i found suitable bcuz its such a nice paper where examiners don't go crazy or drunk when doing it..lol XD)
so anyway if you have any question ask here ^__^..and lets all help each other

 

[AStarHunter]

okay, there was this question for the test and result for dilute nitric acid so i wrote :
Test: Add universal indicator solution
Result:Orange colour
Is that correct ? :unknown:

 

[Adahshan]

wait nitric acid is a strong acid.

 

[AStarHunter]

Ya, but they said dilute so i thought it would be orange. I`m really not sure :/

 

[xIshtar]

okay, there was this question for the test and result for dilute nitric acid so i wrote :
Test: Add universal indicator solution
Result:Orange colour
Is that correct ? :unknown:

Dilute implies that it is weaker and thus has a lower acidity. I believe orange or yellow would be correct.. Is the pH known?
Alternatively, if it is the only acid you have to test for from a group, litmus paper would be acceptable, which is easier to describe

If you have any questions, I would be happy to answer them..

I wish everyone the best of luck tomorrow

 

[HyDraZin3]

Hey guys, i have a doubt
Here is the Link:-http://www.xtremepapers.me/CIE/Cambridge%20IGCSE/0620%20-%20Chemistry/0620_s03_qp_6.pdf
Here in Question 4 (f) they are asking about the identity of solid D and i know that it is a sulphate but how to find out if it is a hydrated sulphate or not?

 

[xIshtar]

Hey guys, i have a doubt
Here is the Link:-http://www.xtremepapers.me/CIE/Cambridge%20IGCSE/0620%20-%20Chemistry/0620_s03_qp_6.pdf
Here in Question 4 (f) they are asking about the identity of solid D and i know that it is a sulphate but how to find out if it is a hydrated sulphate or not?

If it is hydrated, when heated condensation would form. As there was condensation formed when heated, it is hydrated.

 

[narutogirl]

okay, there was this question for the test and result for dilute nitric acid so i wrote :
Test: Add universal indicator solution
Result:Orange colour
Is that correct ? :unknown:

well in my school we never really use universal indicator unless they ask for it...well you could use damp blue litmus paper it turns it red...
extra: if they are testing if it is an acid or not, you could use an alkaline like sodium carbonate, if it reacts and gives everfessence then it is an acid....

sorry i made a mistake(i wrote sodium hyroxide with nitric acid makes everfessence but ofcourse it can't becuase there is no carbon dioxide released..so i am sorry for that mistake)

 

[skinnyboyfat]

can some1 plz help me with appratus names.....paper tommoroow!!!!....plz chemist narutogirl.... :unknown:

 

[narutogirl]

can some1 plz help me with appratus names.....paper tommoroow!!!!....plz chemist narutogirl.... :unknown:

so here is a file that could help you..i didn't do it, i actually found it on a recent forum here..so no credits
so i hope it helps ^_^ ( btw i don't really like chemistry but chemist narutogirl sounds cool, lol )

 

[xIshtar]

can some1 plz help me with appratus names.....paper tommoroow!!!!....plz chemist narutogirl.... :unknown:

so here is a file that could help you..i didn't do it, i actually found it on a recent forum here..so no credits
so i hope it helps ^_^ ( btw i don't really like chemistry but chemist narutogirl sounds cool, lol )

Thanks for the notes
Hopefully Chemistry Paper 6 will be a good one..

I have a couple of questions which I hoped you could answer...
If you half the concentration, but use the same volume as before, half the product will be produced right?
If you half the amount that you are dissolving, the temperature change will fall, as it is less saturated...
What will happen to the rate of reaction in this case though?
If you double the volume of solvent used, will this cause a slower or faster rate of reaction?

 

[haochen]

can some1 plz help me with appratus names.....paper tommoroow!!!!....plz chemist narutogirl.... :unknown:

so here is a file that could help you..i didn't do it, i actually found it on a recent forum here..so no credits
so i hope it helps ^_^ ( btw i don't really like chemistry but chemist narutogirl sounds cool, lol )

we dont need some of it

 

[skinnyboyfat]

can some1 plz help me with appratus names.....paper tommoroow!!!!....plz chemist narutogirl.... :unknown:

so here is a file that could help you..i didn't do it, i actually found it on a recent forum here..so no credits
so i hope it helps ^_^ ( btw i don't really like chemistry but chemist narutogirl sounds cool, lol )

that helped a lot...thanks ..btw u dont like chemistry...i think i tollaly know what u mean...see u around

 

[haochen]

Thanks for the notes
Hopefully Chemistry Paper 6 will be a good one..

I have a couple of questions which I hoped you could answer...
If you half the concentration, but use the same volume as before, half the product will be produced right?
If you half the amount that you are dissolving, the temperature change will fall, as it is less saturated...
What will happen to the rate of reaction in this case though?
If you double the volume of solvent used, will this cause a slower or faster rate of reaction?

if u double the solid then temp will rise by double.
if u double the liquid then the temp will decrease by half.(because more water molecule ids present so it absorb the heat)
if half the concentration is used, half the product (as u said )
if concentration doubled the rate of reaction will also increase

hope that helped

 

[xIshtar]

Thanks for the notes
Hopefully Chemistry Paper 6 will be a good one..

I have a couple of questions which I hoped you could answer...
If you half the concentration, but use the same volume as before, half the product will be produced right?
If you half the amount that you are dissolving, the temperature change will fall, as it is less saturated...
What will happen to the rate of reaction in this case though?
If you double the volume of solvent used, will this cause a slower or faster rate of reaction?

if u double the solid then temp will rise by double.
if u double the liquid then the temp will decrease by half.(because more water molecule ids present so it absorb the heat)
if half the concentration is used, half the product (as u said )
if concentration doubled the rate of reaction will also increase

hope that helped

Thanks, you helped a lot.. What would the overall effect on the rate of reaction be though. With a lower temperature would it not mean a slower rate?

 

[haochen]

if the temp is lowered the reaction rate will decrease (exothermic) (depending on the reaction)
if there is an equation , look at it.
if the forward reaction is exothermic, increasing the temp will decrease the rate of reaction.
if the forward reaction is endothermic, increasing the temp will increase the rate of reaction.

for pressure (for reversible reaction only) :
increase the pressure will shift the equilibrium to the low mole side (count the number in front of the symbol only not inside)
decrease the pressure will shift the equilibrium to the high mole side.


hope that helped

 

[xIshtar]

if the temp is lowered the reaction rate will decrease (exothermic) (depending on the reaction)
if there is an equation , look at it.
if the forward reaction is exothermic, increasing the temp will decrease the rate of reaction.
if the forward reaction is endothermic, increasing the temp will increase the rate of reaction.

for pressure (for reversible reaction only) :
increase the pressure will shift the equilibrium to the low mole side (count the number in front of the symbol only not inside)
decrease the pressure will shift the equilibrium to the high mole side.


hope that helped

Thanks

 

[haochen]

if the temp is lowered the reaction rate will decrease (exothermic) (depending on the reaction)
if there is an equation , look at it.
if the forward reaction is exothermic, increasing the temp will decrease the rate of reaction.
if the forward reaction is endothermic, increasing the temp will increase the rate of reaction.

for pressure (for reversible reaction only) :
increase the pressure will shift the equilibrium to the low mole side (count the number in front of the symbol only not inside)
decrease the pressure will shift the equilibrium to the high mole side.


hope that helped

Thanks

ur welcm

 

[shan5674]

hey can some one give me the name of a solvent that can be used for chromatography pleasee

 

[AStarHunter]

okay, there was this question for the test and result for dilute nitric acid so i wrote :
Test: Add universal indicator solution
Result:Orange colour
Is that correct ? :unknown:

Dilute implies that it is weaker and thus has a lower acidity. I believe orange or yellow would be correct.. Is the pH known?
Alternatively, if it is the only acid you have to test for from a group, litmus paper would be acceptable, which is easier to describe

If you have any questions, I would be happy to answer them..

I wish everyone the best of luck tomorrow

no, the pH wasn`t known :unknown: but, is it alright to say universal indicator solution
Oh and thnx for the answer