IGCSE/GCSE/O & A Level/IB/University Student Forum
Qualification => Subject Doubts => IGCSE/ GCSE => Sciences => Topic started by: killzone on June 13, 2009, 11:08:32 am
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Hey guys i want some one to tell me the answer about the question that said that an element had a proton number of 18 and the next one is element T or sth like that
WAS THE ANSWER ~!
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i sed one more shell or smthng
u noe cuz periods give u the number of shells
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Hey guys i want some one to tell me the answer about the question that said that an element had a proton number of 18 and the next one is element T or sth like that
WAS THE ANSWER ~!
wat did u write???
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for argon being used in the filament, i chose the tick for it being more abundant in air compared to helium, and the cross for it being less dense.
hw abt u guys?
and for the group 7 thing, i did increasing boiling and melting points, how abt u u guys?
and for the which is not the use of stainless steel, i said railway. how abt u guys?
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4 the 1st ans.....its was cross croxx..
none of da above was correct....
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oh, bt argon is more abundant in air, 0.93%.
bt helium is very less, 0.02%
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really..........these gases compose of 0.8% of the air.....
so do u think they r abundant....????
78% nitro
21% oxygen
1% other gases....out of these 0.2% is co2!!!!!
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being more abundant is correct because argon is much more available than helium..so its much cheaper
and for gp7 m.p and b.p do increase thats why they change from gases to solids
and for stainless steel ofcourse it's railway lines because it was written that its very expensive so according to logic its right
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i think maybe u misunderstood da q..
they said argon is used in filament lamps...so that they can last 4 a longer time......
which of da following properties is suitable for its use.....
so da options they gave wr totally irrelevant to its use...
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being more abundant is correct because argon is much more available than helium..so its much cheaper
and for gp7 m.p and b.p do increase thats why they change from gases to solids
and for stainless steel ofcourse it's railway lines because it was written that its very expensive so according to logic its right
no dude.....ARGON IS USED BECAUSE IT IS UNREACTIVE[INERT]
ITS NOT used because it is abundent or denser...tec..
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wateva ppl............just enjoy ur vacation ppl...................who cares of it wz abundant or denser 8)
we finished exams..so dont let ur wrong answers affect ur vacation 8)
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so why dont they use xenon if its about unreactivity
its just because its abundant so it would be the cheapest
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xenon is bright...so its used in car lights.... :P :P
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no man its bright only when a current is passed through it
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of course.......i was kiddin.....y dont u ask the chemical engineers
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no seriously it makes perfect sense
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okay boombastic ur right.
There is nothing got to do with it being heavier or abundant. They asked what makes it suitable for filament lamps.
Helium is also abundant if u guys don't know. It is used in weather balloons and in scuba diving(80%helium and 20%oxygen mixture, although oxygen is more abundant) .
The reason why argon is used in filament bulbs is because the metal filament will not burn in Argon and it reduces evaporation of the metal filament.
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i know that they put inert gases because they are unreactive...there are many inert gases..so why did they choose argon..because its the easiest and cheapest gas to obtain...and they put helium in weather balloons just bcz its less dense than air
so y put an unreactive gas that is hard to obtain
it makes sense man
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no no no...............
argon is the CHEAPEST WAY!!!!!!!!!!!!!!!! :-\
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argon has the ability to reduce evaporation of the metal filament. U want to assume urs is right go on. I'm just telling the right reason
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MY DEAR....
The inert gas can be argon, krypton, or xenon. If the manufacturer wants to go cheap, argon is used. For a little better performance with an only slightly higher cost, krypton is used and this is common. For slightly better performance than krypton, xenon is used.
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man all inert gases reduce evaporation of the metal filament not just argon
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MY DEAR....
The inert gas can be argon, krypton, or xenon. If the manufacturer wants to go cheap, argon is used. For a little better performance with an only slightly higher cost, krypton is used and this is common. For slightly better performance than krypton, xenon is used.
i think i said it ,,anyone can be used ....look above..sighs
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man all inert gases reduce evaporation of the metal filament not just argon
Argon is more efficient.
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no i was replying to nid404
so ur convinced mr.boombastic
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its cost-effective.....as well
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IGs whether u believe it or not...argon is used for other reasons than being abundant.
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wat abt the 3rd questin....abt naco3 used at different temp....?
wat did u rite
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wat abt the 3rd questin....abt naco3 used at different temp....?
wat did u rite
i don't remember the q. can u tell me what it was abt??
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well i looked it up in chem. books and no book says that it has other functions than being unreactive
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well i looked it up in chem. books and no book says that it has other functions than being unreactive
so wat did i say???
@nid....it was that q in which a table was shown...filter funnel,clock ,thermometer..
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i think it was everything except filter funnel. because they wanted to note the time taken for bubbles to stop.
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mr.boombastic im with u i was replying to nid404
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mr.boombastic im with u i was replying to nid404
ooops my bad... ;) srry
and nid i wrote da same..
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mr.boombastic im with u i was replying to nid404
boombastic also said it was neither of the properties. Argon over helium is for efficiency. At high temp helium is not as effective as argon.At higher temp helium diffuses faster.
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wat diffusion..they r put into small bulbs
wat kind of diffusion
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also another point
they are comparing between argon and helium..but if they were not comparing ofcourse being abundant is wrong
due to comparison..it is bcz its abundant...i even asked all my chem teachers
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my mission now is to convince u nid hehe dont take it personally
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my mission now is to convince u nid hehe dont take it personally
haha......
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u r convinced boombastic ryt??
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u r convinced boombastic ryt??
wat do u mean??
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the properties mention were possesed by Argon n Helium BUT the SPECIFICALLY asked WHICH PROPERTY BELOW IS THE RESON for RGON to be used in the bulb !!
the propertiec which wer mention were neither n
soo
it was
x x
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no the q was why not helium is used in bulbs the only reason is that argon is abundant..they both have the same properties(unreactive)
so the only reason that argon is used rather than helium is that its abundant(cheaper to obtain)
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they werent asking wat r the properties of argon in general...they were comparing the gases
y is argon used RATHER than helium...but if there were no comparison..ofcourse being abundant isnt the reason for being in the bulbs
but y is it used rather than helium then it is bcz its abundant
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I think argon is used because it produces light of a particular colour.
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Hey guys i want some one to tell me the answer about the question that said that an element had a proton number of 18 and the next one is element T or sth like that
WAS THE ANSWER ~!
wat did u write???
i wrote that it has one more shell, cuz argon is in group eight having 18 protons and the next one has 19 nd its a metal in group 1 so it has one more shell containing one electron..
but i am not sure
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the only reason they put argon is bcz its unreactive
check ur chem books guys..its written there
so there is no difference between helium and argon they r both unreactive...so the reason is according to logic using a gas which is more abundant is much easier and cheaper..pure logic
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the only reason they put argon is bcz its unreactive
check ur chem books guys..its written there
so there is no difference between helium and argon they r both unreactive...so the reason is according to logic using a gas which is more abundant is much easier and cheaper..pure logic
I think you are 100% correct , wat u r saying makes perfect sense .,,, i also wrote that :)
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MY DEAR....
The inert gas can be argon, krypton, or xenon. If the manufacturer wants to go cheap, argon is used. For a little better performance with an only slightly higher cost, krypton is used and this is common. For slightly better performance than krypton, xenon is used.
the fact mention above is da perfect one...
i told u 4rm my very.own ch.book!!!!!
they DIDNT ASKED GENERALLY.....THEY ASKED WITH RESPECT OT DA QUESTION ABT LAMPS!!!!!
Y DONT U GET IT?????? :(
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both helium and argon are unreactive..but theres 0.933% argon
and like 0.0005% helium in the air.
so argon is more abundant in air making it more efficient and easier to use in light bulbs than helium.
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f9.....stick to watever ur mind says......
but da logic...is that its used cuz its inert.........UNREACTIVE!!!!!!!!!!!!!!!!!!!!
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people no fighting...it's only an argon!! not worth it ;D
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lol
yes argon IS unreactive :P
but so is helium :P
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but why argon not helium they're both unreactive??
so obviously bcz its more cheaper to obtain a gas that is found large amounts respectively
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this is da best explanation i can give!!!!!!!
MY DEAR....
The inert gas can be argon, krypton, or xenon. If the manufacturer wants to go cheap, argon is used. For a little better performance with an only slightly higher cost, krypton is used and this is common. For slightly better performance than krypton, xenon is used.
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boombastic u mean the answer is
tick cross??
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boombastic u mean the answer is
tick cross??
NO!!!!!!!!!!!!!!!!!!!!!!!!!!!!
ITS
X X
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guys wht did u write for the stainless steel questions and the one about the fractional distillation (was it petrol or parrafin?)
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people no fighting...it's only an argon!! not worth it ;D
xcuse me :P...
v r not fighting.....just a hot discussion goin on!!!!!!!!!!!!!!!!
wanna join??
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we r going to do this all day long..actually i asked all my teachers and they agree with me..
and IG girl its railway and parafin
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people no fighting...it's only an argon!! not worth it ;D
xcuse me :P...
v r not fighting.....just a hot discussion goin on!!!!!!!!!!!!!!!!
wanna join??
why not?! but it's becoming pretty boring with argon!
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then check this website out...http://en.wikipedia.org/wiki/Stainless_steel
It says and will quote ""Common uses of stainless steel are cutlery and watch straps."
I chose cutlery!
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the q was where is stainless steel not used
so its railway lines
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the q was where is stainless steel not used
so its railway lines
oh right...got one mistake then ;D cuz i thought they said where is it used!!
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it became boring with the argon ryt
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it became boring with the argon ryt
yes very boring.... my answer for that q was tick and cross!
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finally someone who is smart :D
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finally someone who is smart :D
\
i already proved u wrong!!!!
and ig girl.....then gave in bold letters NOT
y did u rite cutlery
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ig girl dnt worry u did correct abt the argon
good job
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yeah...rite....... :P :P :P :P
i am waiting 4 da mark scheme!!!lol
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argon is more abundant and more dense than helium thats why helium is used for filling airships and balloons ;)
so its a tick , cross hence the answer is B ;D
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Mr.Boombastic i was in a rush...so didnt concentrate that much on the question...
Lets hope that our answer is right!!
yes that's what i did!!
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Mr.Boombastic i was in a rush...so didnt concentrate that much on the question...
Lets hope that our answer is right!!
yes that's what i did!!
WHY THE RUSH!!!!!!
THEY GAVE ample time.....
i seriously completed the paper exactly 25min early.........
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Mr.Boombastic i was in a rush...so didnt concentrate that much on the question...
Lets hope that our answer is right!!
yes that's what i did!!
WHY THE RUSH!!!!!!
THEY GAVE ample time.....
i seriously completed the paper exactly 25min early.........
it's just my mistake...when im in an exam reading the question i skip many words so i understand the question in the wrong way!!
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i completely agree with u IG, they're both unreactive bt argon is used cuz it more abundant (0.93%) than helium in the atmosphere. and its not less dense than helium, so it's tick cross :) :)
and IG, if ur teacher said its right, den dats great!
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maybe u gys r right!!! ::)
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maybe u gys r right!!! ::)
hehe u gave up?! lol
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maybe u gys r right!!! ::)
hehe u gave up?! lol
its ok, it happens :)
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no i didnt......
as u can see i tried to explain u every thing i could...but it seems...u dont like like it
and my reps hav gone down 4rm 9 to 5 to 4 to2!!!!!!!!!!!
so i just dont get it!!!
r u an average student??
answer it honestly!!! :)
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no i didnt......
as u can see i tried to explain u every thing i could...but it seems...u dont like like it
and my reps hav gone down 4rm 9 to 5 to 4 to2!!!!!!!!!!!
so i just dont get it!!!
r u an average student??
answer it honestly!!! :)
my reps are getting down everytime...i honestly dont care about it anymore..
No im not an average student....was the top in my class this year in the mocks!! ;D
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well i put X X too so .. ?? i think its right..
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well i put X X too so .. ?? i think its right..
hmm dont think about it ;) enjoy ur summer!
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hey was it petrol or parafin?
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parrafin!!!!!
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ppr ws easy compard 2 rest?? rite??? no rest vr also easy bt this ws da most easiest......
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agreed!!!!
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agree again!!
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hey can anyone xplain abt alevel i knw nufin abt it...... see Help topic in alvl sec.. plz i need help......
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hey can anyone xplain abt alevel i knw nufin abt it...... see Help topic in alvl sec.. plz i need help......
wow AS levels comes after o-level...2 AS levels is equivelant to 1 A level!!
A levels depends on the university u r going to...some want it and some dont!
If u r thinking to study in the Uk then u'll definitely need 3 A-levels!
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I dont think so. As a foreign student uk universities will charge you extortionate rates, and they are so eager to get your money I'm sure they will take you no matter what your grades or how many A levels.
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AS levels is the first year of Alevels. So those taking Alevels will have to give an exam in the first year. The second year is Alevels for which u give another exam.
I have taken A levels. So I have my AS same time next year and A levels in November next year.(i'm doing 18months and not 2 full years). So I get six months to prepare for entrance exams here
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guys wht did u write for the stainless steel questions and the one about the fractional distillation (was it petrol or parrafin?)
for fractional distillation was parrafin..because it says used in jet or something..
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I dont think so. As a foreign student uk universities will charge you extortionate rates, and they are so eager to get your money I'm sure they will take you no matter what your grades or how many A levels.
we had here in kuwait an exhibition where all the universities were there..all of them wanted A levels...3 of them...and not less than a B!! :o
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Different country different system. What happens if you decide you cant stand physics?
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okay boombastic ur right.
There is nothing got to do with it being heavier or abundant. They asked what makes it suitable for filament lamps.
Helium is also abundant if u guys don't know. It is used in weather balloons and in scuba diving(80%helium and 20%oxygen mixture, although oxygen is more abundant) .
The reason why argon is used in filament bulbs is because the metal filament will not burn in Argon and it reduces evaporation of the metal filament.
i know im a bit late for this topic
i was out all day
anyways i wanted to say dat my dad is a chemical engineer and he sed being abundant is da probably da ryt answer
cos it is and dey dnt expect us to know all da properties of argon as opposed to helium
bt they do expect us to knw da composition of air and it contains more argon
and i quoted this to say dat you shud compare da number of weather baloons and scuba diving kits to light bulbs
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I think argon is used because it produces light of a particular colour.
and lol im not a physics ig student but dsnt light contain alot of colours 0_0
bt i think it may also b a reason as dey dnt use argon in white light as far as i know
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shafiq_92libra ur my man finally someone who has some sense ive been trying to convince everybody here but nobody was convinced...thank u man u made my day
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shafiq_92libra ur my man finally someone who has some sense ive been trying to convince everybody here but nobody was convinced...thank u man u made my day
srsly, thanks :)
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hey guys anyone planning to do IBs next year?
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yup, ill be doing the diploma which is challenging
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hey i dont remember which question this was but was one ur answers for the oxide of something turning the litmus paper blue calcium??
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hey i dont remember which question this was but was one ur answers for the oxide of something turning the litmus paper blue calcium??
turning the paper blue means that it's alkali.....only metals form basic oxides so it's calcium!! u r right!!
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being more abundant is correct because argon is much more available than helium..so its much cheaper
and for gp7 m.p and b.p do increase thats why they change from gases to solids
and for stainless steel ofcourse it's railway lines because it was written that its very expensive so according to logic its right
no dude.....ARGON IS USED BECAUSE IT IS UNREACTIVE[INERT]
ITS NOT used because it is abundent or denser...tec..
By the way all group zero gases are inert n they do not react argon i agree creates an inert atmosphere but der dey wanted to noe wen both of dem r inert den why onli argon is used so it has to be bcoz it is more abundantly found compared to the others
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oh guys....loll....ur still afta dat poor ques??
leave it...its ova!!
njoy ur lyfs for heavens sake!!!
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zara's ryt just 4get enjoy chillax and PARTAAYYY :D :D
after all its onlyyy 1 mark !!!
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zara's ryt just 4get enjoy chillax and PARTAAYYY :D :D
after all its onlyyy 1 mark !!!
dude this paper is only 4r 40 marks so 1 mark is alot n if da treshold is low den ...........................
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oh god...madiha...chill yaar...
so wat if ur losin a mrk...can u chng it now??no rite?so...just leave it...
n ya By the way chk out the Dawaa topic...i posted sumthing whch u might fynd useful...
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hey guyzz wht did u rite abt the stainless steel thing
i rote factory pipes it was sumthin like it is expensive n doesnt corrode i dontt rememba does ny1 remeba the q hea
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oh god...madiha...chill yaar...
so wat if ur losin a mrk...can u chng it now??no rite?so...just leave it...
n ya By the way chk out the Dawaa topic...i posted sumthing whch u might fynd useful...
yup i chkd it out its nyc Thanks n ya one correction its madeeha
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oh god...madiha...chill yaar...
so wat if ur losin a mrk...can u chng it now??no rite?so...just leave it...
n ya By the way chk out the Dawaa topic...i posted sumthing whch u might fynd useful...
yup i chkd it out its nyc Thanks n ya one correction its madeeha
oopss.....srry....madeeha... ;D
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oh god...madiha...chill yaar...
so wat if ur losin a mrk...can u chng it now??no rite?so...just leave it...
n ya By the way chk out the Dawaa topic...i posted sumthing whch u might fynd useful...
yup i chkd it out its nyc Thanks n ya one correction its madeeha
oopss.....srry....madeeha... ;D
zara did u go to da prom
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hmm i hink i remember the q.. i m sure i didnt ryt factory pipes though
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oh god...madiha...chill yaar...
so wat if ur losin a mrk...can u chng it now??no rite?so...just leave it...
n ya By the way chk out the Dawaa topic...i posted sumthing whch u might fynd useful...
yup i chkd it out its nyc Thanks n ya one correction its madeeha
oopss.....srry....madeeha... ;D
zara did u go to da prom
nopes :'(
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oh god...madiha...chill yaar...
so wat if ur losin a mrk...can u chng it now??no rite?so...just leave it...
n ya By the way chk out the Dawaa topic...i posted sumthing whch u might fynd useful...
yup i chkd it out its nyc Thanks n ya one correction its madeeha
oopss.....srry....madeeha... ;D
zara did u go to da prom
nopes :'(
yyy
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hey guyzz wht did u rite abt the stainless steel thing
i rote factory pipes it was sumthin like it is expensive n doesnt corrode i dontt rememba does ny1 remeba the q hea
hmmm....well...if ur discussin abt this q...i rote railway lines....cz they said its too expensive...so i don't think theyll use it for the railways....pipes there r chances for it tho but vry less...
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hmm i hink i remember the q.. i m sure i didnt ryt factory pipes though
so can u like post it plz
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hmm i hink i remember the q.. i m sure i didnt ryt factory pipes though
so can u like post it plz
i dunt relly remember wht answer i rote.. if u can could u post the choices nd maybe i might remember :)
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the q was like..
Stainless steel is very expensive...select whch one is NOT made frm the it or wont b appropriate...sumthing like dat..
choices were..
cutlery
railway lines
chemical pipes
don't remember(but surely it was rong)
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oh god...madiha...chill yaar...
so wat if ur losin a mrk...can u chng it now??no rite?so...just leave it...
n ya By the way chk out the Dawaa topic...i posted sumthing whch u might fynd useful...
yup i chkd it out its nyc Thanks n ya one correction its madeeha
oopss.....srry....madeeha... ;D
zara did u go to da prom
nopes :'(
yyy
hmmm.....dude...long story....
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hmm i hink i remember the q.. i m sure i didnt ryt factory pipes though
so can u like post it plz
i dunt relly remember wht answer i rote.. if u can could u post the choices nd maybe i might remember :)
cutlery
railway lines
factory pipes
n the 4th one i don rememba
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hmm i hink i remember the q.. i m sure i didnt ryt factory pipes though
so can u like post it plz
i dunt relly remember wht answer i rote.. if u can could u post the choices nd maybe i might remember :)
cutlery
railway lines
factory pipes
n the 4th one i don rememba
ha...loll....madee...i just said the same thing abov...loll
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ya i think most probably i wrote chemical pipeline cause they wont corrode no matter how strong the chemical is
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omg chill guys.....it's ur vacation why do u have to worry about something u did like 1 week ago or even more?!!
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By the way chem pipelines are wrong
da nyt b4 da exam iwas out wid friends lol "study grouping" and playing cards
and den my friends dad came in so we hid all da card wid papers
and i acted like i was askin this question
which one of dese uses stainless steel
and chemical plant was 1 of da options
and his dad sed chem plants and we chekd da answer scheme and it was ryt
so dats why i remember =D
lol soory for da anecdote xDD
oh and da question asked which 1 dsnt use stainless steel
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By the way chem pipelines are wrong
da nyt b4 da exam iwas out wid friends lol "study grouping" and playing cards
and den my friends dad came in so we hid all da card wid papers
and i acted like i was askin this question
which one of dese uses stainless steel
and chemical plant was 1 of da options
and his dad sed chem plants and we chekd da answer scheme and it was ryt
so dats why i remember =D
lol soory for da anecdote xDD
oh and da question asked which 1 dsnt use stainless steel
Thanks