Chemistey Doubts

[gary221]

http://www.xtremepapers.me/CIE/Cambridge%20IGCSE/0620%20-%20Chemistry/0620_w08_qp_1.pdf


Q 35 what is it i didnt get anything!!!!!!!!!!

the ans is D, i think!
look u hve to keep the rusting process in mind
iron + oxygen = iron oxide
thus the O2 in the test tube will be used up and the tube will fill wth water

hpe u gt it!!

thnx alot

s ok!
just keep d doubts rolling in!!

 

[MohammedNoor]

Q 22 has two litmus paper y????

http://www.xtremepapers.me/CIE/Cambridg ... 8_qp_1.pdf

 

[gary221]

Q 22 has two litmus paper y????

http://www.xtremepapers.me/CIE/Cambridg ... 8_qp_1.pdf

the ans is D
thr r 2 litmus ppr to test the gas given off
red is 4 ammonia and blue is 4 chlorine

 

[MohammedNoor]

Q 22 has two litmus paper y????

http://www.xtremepapers.me/CIE/Cambridg ... 8_qp_1.pdf

the ans is D
thr r 2 litmus ppr to test the gas given off
red is 4 ammonia and blue is 4 chlorine

thnx again

 

[TSZ]

for question 22....when an ammonium salts reacts with an alkali it produces salt, water and ammonia gas so the litmus shud turn blue as ammonia is basic gas.....in experiment 2 acid and alkali react to form salt and water so there shud be no change to te litmus so the ans shud be D

 

[MohammedNoor]

ok thnaks everyone for their individual help.............hope everyones exam goes good tomorrow and a bright future for everyone

 

[MohammedNoor]

ok thnaks everyone for their individual help.............hope everyones exam goes good tomorrow and a bright future for everyone

bye bye

 

[She7taman]

Q 22 has two litmus paper y????

http://www.xtremepapers.me/CIE/Cambridg ... 8_qp_1.pdf

That part is pretty obvious, if you have one litmus paper, and it's blue, and an alkaline gas is given off, there would be no change, because it is already blue. How would you know whether that gas was really alkaline or just neutral? The red litmus paper checks for alkaline gases while the blue paper checks for acidic gases.

The question is a tad tricky though, but the answer would be D. This is because ammonia would be released in the first test tube, as is expected when adding an ammonium salt with NaOH and heating. In the other test tube, there would be no decomposition, no reason for the ammonia to be released, so no change.

Edit: a bunch of people beat me to it.

 

[MohammedNoor]

ok thnaks everyone for their individual help.............hope everyones exam goes good tomorrow and a bright future for everyone

bye bye

if anyone liked this post plz click the thnx button

 

[gary221]

ok thnaks everyone for their individual help.............hope everyones exam goes good tomorrow and a bright future for everyone

same here!!

 

[MohammedNoor]

ok thnaks everyone for their individual help.............hope everyones exam goes good tomorrow and a bright future for everyone

same here!!

here what????????????????

 

[gary221]

ok thnaks everyone for their individual help.............hope everyones exam goes good tomorrow and a bright future for everyone

same here!!

here what????????????????

here the exam goes well thts wht!!

i hve chem ppr 1 n comp ppr 3 tomrrw

 

[gary221]

wish me luck!!

 

[MohammedNoor]

wish me luck!!

wishing u luck luckily i have only chemistry paper 1

 

[gary221]

wish me luck!!

wishing u luck luckily i have only chemistry paper 1

good 4 u!!!
which country r u frm????

 

[MohammedNoor]

wish me luck!!

wishing u luck luckily i have only chemistry paper 1

good 4 u!!!
which country r u frm????

u r frm where

 

[She7taman]

I'm starting to realize that there is a stunning lack of moderation in this forum. Stop derailing the thread with irrelevant and useless posts. If you want to chat with someone, PM them. Otherwise, if your post doesn't contribute to the topic, don't post it.

 

[MohammedNoor]

I'm starting to realize that there is a stunning lack of moderation in this forum. Stop derailing the thread with irrelevant and useless posts. If you want to chat with someone, PM them. Otherwise, if your post doesn't contribute to the topic, don't post it.

u r right!!!!!!!!!!!!!!!!!!

 

[gary221]

I'm starting to realize that there is a stunning lack of moderation in this forum. Stop derailing the thread with irrelevant and useless posts. If you want to chat with someone, PM them. Otherwise, if your post doesn't contribute to the topic, don't post it.

oops !!! srry if i offende u or brke sum kind of rule but we wre studying 4 quite sum time
n just wishing each other luck

no offence dude!! :good:

 

[MohammedNoor]

I'm starting to realize that there is a stunning lack of moderation in this forum. Stop derailing the thread with irrelevant and useless posts. If you want to chat with someone, PM them. Otherwise, if your post doesn't contribute to the topic, don't post it.

oops !!! srry if i offende u or brke sum kind of rule but we wre studying 4 quite sum time
n just wishing each other luck

no offence dude!! :good:

U r right too gary nd i (noor) were claering our doubts.......and wishng luck to each other............sorry for breaking any rules