I'm in.

Kunlexic: Chemistry
student of nairaland,where are you?Either you a jambite or a student of
Polytechnic and University lets meet here and solve chemistry
questions,it may be the one for O-level,Jamb and advanced chemistry.u
are all welcome as u contribute.
For physics thread,click on dis link below
https://www.nairaland.com/1404215/nairaland-physics-gurus#17840190

Xtyna9ja: I'm in.

welcome

denniece1:
ok just reason @kunlexics quest..is there any tin lyk S^2+ since u say its sulphur(16).?

i tot i said i md a mistake.16 is atomic mass of oxygn,nd its s^2- whch is sulphur

denniece1:
22

hw,xplain

Mikebis: i tot i said i md a mistake.16 is atomic mass of oxygn,nd its s^2- whch is sulphur

But kunlexic said X^2+ not X^2-

Mikebis: hw,xplain

X^2+ meaning it has lost 2 electrons...nd 4rm d electro. config u gave it was 20electrons...since it has already lost 2 electrons then it originally had 22electrons which makes d atomic no. 22

Mikebis: hw,xplain

assuming u said X^2- then d atomic no will be 18.

Yea u gat it@kunlexic

denniece1:
assuming u said X^2- then d atomic no will be 18.

sinc d cnfigratn iz 18 already,dey cnt expect u to use it lik dat,xo u wil av to use d x^2-..wich wil make it 16

Kendzyma: sinc d cnfigratn iz 18 already,dey cnt expect u to use it lik dat,xo u wil av to use d x^2-..wich wil make it 16

but the question was X^2+ not X^2- ...they are 2 diff. things.

Kunlexic: Answer did simple 1
what is the atomic number of an elemrnt whose ion X^2+ has electronic configuration of 1s2 2s2 2p6 3s2 3p6?

...i hav bin observin d thread so far n i tink u guys are takin dis question 2 far...itz over a page now and u are still solvin dis....well, d ansa is 16:::Explanation= for any X with superscript negative number i.e X^2-; it means addition of electrons..while, if superscript positive number i.e X^2+ it mean substraction of electrons...and remember Electronic conf. Is based on electrons...i hope dis would help...bring more questions plz...stil remain Uncle Fetus

Fetus: ...i hav bin observin d thread so far n i tink u guys are takin dis question 2 far...itz over a page now and u are still solvin dis....well, d ansa is 16:::Explanation= for any X with superscript negative number i.e X^2-; it means addition of electrons..while, if superscript positive number i.e X^2+ it mean substraction of electrons...and remember Electronic conf. Is based on electrons...i hope dis would help...bring more questions plz...stil remain Uncle Fetus

bro,it can't be 16,since it is not a negative ion...am still saying the ansa is 20,what we re saying is simple.If u count the no of electrons on X^2+,u will see it s 18 and since b4 it turns to positive ion,the atom has lose 2 electons out of its electons....if u agree dat the answer is 20,like this post.....@ lateef,i think u be baba 4 chemistry,pls help us solve dis matter.

Fetus: ...i hav bin observin d thread so far n i tink u guys are takin dis question 2 far...itz over a page now and u are still solvin dis....well, d ansa is 16:::Explanation= for any X with superscript negative number i.e X^2-; it means addition of electrons..while, if superscript positive number i.e X^2+ it mean substraction of electrons...and remember Electronic conf. Is based on electrons...i hope dis would help...bring more questions plz...stil remain Uncle Fetus

thank u xo much dat is wat av bn sayn since,i said an ion avn negtv wll av 2 b added,nd an ion avn positv wll av to b subt,nd i gat ma ansa to b 16,dat means d questn supose to b x^2- nt x^2+.

Kunlexic: bro,it can't be 16,since it is not a negative ion...am still saying the ansa is 20,what we re saying is simple.If u count the no of electrons on X^2+,u will see it s 18 and since b4 it turns to positive ion,the atom has lose 2 electons out of its electons....if u agree dat the answer is 20,like this post.....@ lateef,i think u be baba 4 chemistry,pls help us solve dis matter.

dat means u re wrng.it supose 2 b x^2- nd nt x^2+

Well, if u tink i'm wrong no problem...i vowed never 2 argue...my records in kemis3 speak 4 me....only if u knw me...more questions plz++uncle fetus....

Mikebis: dat means u re wrng.it supose 2 b x^2- nd nt x^2+

am nt wrong wit d questn,its x^2+

Fetus: Well, if u tink i'm wrong no problem...i vowed never 2 argue...my records in kemis3 speak 4 me....only if u knw me...more questions plz++uncle fetus....

i wll also stop argue cos i knw am correct

Rmb d quest was wat is d atom. no. of X and d electronic configuration given is for X^2+ i.e 2elecrons was subtracted from the 20electrons of X to give the 18electrons of X^2+ written in the quest as 1s2 2s2 2p6 3s2 3p6.

[font=Lucida Sans Unicode][/font]Am in chemistry splash

Whats the difference btw azimuthal and principal quantum number??

denniece1: Rmb d quest was wat is d atom. no. of X and d electronic configuration given is for X^2+ i.e 2elecrons was subtracted from the 20electrons of X to give the 18electrons of X^2+ written in the quest as 1s2 2s2 2p6 3s2 3p6.

ehn,dats d elect.configuratn for x^2+.The questn nw say what will be the atomic no 4 X atom b4 it loses 2 out of his electrons...anyway lets 4get abt dis argue and continue to lets more questn come in...

Odilop: Whats the difference btw azimuthal and principal quantum number??

the azimuthal quantum no shows the energy sub-level in each shell(i.e- s,p,d,f) while the principal quantum shows d shells/energy level(i.e-K,L,M,N shells)

Kunlexic: the azimuthal quantum no shows the energy sub-level in each shell(i.e- s,p,d,f) while the principal quantum shows d shells/energy level(i.e-K,L,M,N shells)

yes boss

if 0.1faraday of electricity of cuso4 is passed,the maximum weight of cu deposited on the cathode is?(molar mass of cu=64)

wow! Love dzzz letz av dz as intro
1)balance d equatn
o2(g)---->o3(g)
if d absolute entropies of oxygen and ozone are 204.8 and 237.4j/molk respectvly,calculate standard entropy change in the reaction cited.


2)20cm3 of a gaseous hydrocarbon were mixed with 160cm3 of oxygen(an excess),both at room temperature and later exploded.on cooling to the original temperature of measurement,130cm3 of the residual gaseous mixture was obtained.After passing through conc.koH solution the volume was reduced to 50cm3.The volume in cm3 of o2 used and co2 produced are respectively:
a)80,110
b)48,80
c)30,48
d)110,80


3) (i) p/p (linearly opposed)
(ii)p/p (parallel)
(iii)sp/sp
(iv)sp2/sp2
(v)sp/p (linearly opposed).
Which of these mode(s) of overlappings is/are found in carbon(iv)oxide(co2) moleecule?
A) i,ii,iii only
b)ii,v only
c)i,v only
d)iii,iv,v only


4)20cm3 of a gaseous hydrocarbon were mixed with 120cm3 of oxygen(an excess) and both at room temperature and later exploded.on cooling to original temperature of measurement,100cm3 of residual gaseous mixturee was obtained.After passing through concentrated koH solution,the volume was reduced to 40cm3.ccalculate the molecular formula of the hydrocarbon.
A)C2H4
b)C3H6
c)C2H6
d)C3H4

goodnite!

yinkhar: if 0.1faraday of electricity of cuso4 is passed,the maximum weight of cu deposited on the cathode is?(molar mass of cu=64)

if 64g of cu z deposited by 2f tthen 0.1f will deposit,(0.1 * 64)/2=3.2g

yinkhar: if 0.1faraday of electricity of cuso4 is passed,the maximum weight of cu deposited on the cathode is?(molar mass of cu=64)

...shortcut formular..M=Q*R.M.M/nf * 96500c...where M=mass, Q=it(f), R.M.M=relative molecular mass of d given ion, nf=no of faraday, 96500c= one no of moles.....to d question..Q=0.1F, R.m.m= 64; nf=2(frm electrochemical series) , m=?.....usin d formular now:: M=0.1 * 64 /2*96500=3.32*10^-5 g or 0.000332g.....more questions plz...Uncle fetus.

buzyguy: wow! Love dzzz letz av dz as intro
1)balance d equatn
o2(g)---->o3(g)
if d absolute entropies of oxygen and ozone are 204.8 and 237.4j/molk respectvly,calculate standard entropy change in the reaction cited.


2)20cm3 of a gaseous hydrocarbon were mixed with 160cm3 of oxygen(an excess),both at room temperature and later exploded.on cooling to the original temperature of measurement,130cm3 of the residual gaseous mixture was obtained.After passing through conc.koH solution the volume was reduced to 50cm3.The volume in cm3 of o2 used and co2 produced are respectively:
a)80,110
b)48,80
c)30,48
d)110,80


3) (i) p/p (linearly opposed)
(ii)p/p (parallel)
(iii)sp/sp
(iv)sp2/sp2
(v)sp/p (linearly opposed).
Which of these mode(s) of overlappings is/are found in carbon(iv)oxide(co2) moleecule?
A) i,ii,iii only
b)ii,v only
c)i,v only
d)iii,iv,v only


4)20cm3 of a gaseous hydrocarbon were mixed with 120cm3 of oxygen(an excess) and both at room temperature and later exploded.on cooling to original temperature of measurement,100cm3 of residual gaseous mixturee was obtained.After passing through concentrated koH solution,the volume was reduced to 40cm3.ccalculate the molecular formula of the hydrocarbon.
A)C2H4
b)C3H6
c)C2H6
d)C3H4

goodnite!

.....i'm goin 2 ansa number alone bcus it got no options,,,,as 4 d others i guessed dey are frm d utme pack...dnt make dis thread a mess by bringin questions frm jamb pack..where u hav ur ansa already...bring questions dat u found difficult 2 solve...just an advice...2 question one...3o_2(g)>>2o_3(g) i.e _ means subscript....So_2=204.8j/kmol, So_3=237.4j/kmol...using dis xpression; €S=€S_product- €S_reactant.....€S=2(273.4)-3(204. =546.8 - 614.4= -67.6j/kmol ...where S=entropy, €=change, _=subscript.....#morequestionsplz#...Uncle Fetus

Fetus: .....i'm goin 2 ansa number alone bcus it got no options,,,,as 4 d others i guessed dey are frm d utme pack...dnt make dis thread a mess by bringin questions frm jamb pack..where u hav ur ansa already...bring questions dat u found difficult 2 solve...just an advice...2 question one...3o_2(g)>>2o_3(g) i.e _ means subscript....So_2=204.8j/kmol, So_3=237.4j/kmol...using dis xpression; €S=€S_product- €S_reactant.....€S=2(273.4)-3(204. =546.8 - 614.4= -67.6j/kmol ...where S=entropy, €=change, _=subscript.....#morequestionsplz#...Uncle Fetus

gud trial,
frm d equatn u balanced abov u still av to rearrang their moles to d nearst or least valuee dat is,
3/2o2(g)---->o3(g)
then putting valuuez givez -69.8j/molk as answer.

[quote author=Kunlexic]ah bro,u are wrong...dis it as follows X^2+=2+2+6+2+6=18electrons since its a positive ion with 2 charges,dat means it has given out 2 out of his electrons,so the element is an element with atomic no 20,20 protons and 20 electrons which is calcium not oxygen...pls quote me if i am wrong coz am still a learner. I agree wth u.

denniece1: Rmb d quest was wat is d atom. no. of X and d electronic configuration given is for X^2+ i.e 2elecrons was subtracted from the 20electrons of X to give the 18electrons of X^2+ written in the quest as 1s2 2s2 2p6 3s2 3p6.

the question was about atomic number (no of protons)and ions indicate only loss of electrons. So the answer is just 18.

buzyguy: gud trial,
frm d equatn u balanced abov u still av to rearrang their moles to d nearst or least valuee dat is,
3/2o2(g)---->o3(g)
then putting valuuez givez -69.8j/molk as answer.

,,,datz true....spot on..more questions plz....Uncle fetus8-)