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last SG · 2015-08-19T22:54:00+00:00

Topic : atomic radius Hi! This is from singapore cambridge nov a level exam year 2010,Paper 1 qn 1Qn: which element has the largest atomic radius?BrKKrScSo...

UltimaOnline SG

https://www.dropbox.com/s/yvz3cotvl3r2gt4/20161008_184906-1.jpg?dl=0

https://www.dropbox.com/s/otc8gwvqu6dh0wn/20161008_184909-1.jpg?dl=0

how to distinguish isomer W and X?

why the answer say white solid? phenylamine is colorless-yellow liquid, sodium ethanoate is soluble in water

Alkaline hydrolysis, followed by iodoform test, is a better answer.

You keep making the same type of mindless (ie. lacking mindfulness or situational awareness) mistakes over and over again, you coconaden. Do you really expect to see a "colorless to yellow liquid" under these conditions?

UltimaOnline SG

for this qn, conc hcl given is 0.05 M, so i calculate using nHCl = 0.05 ×10/1000

nH+ = nHCl

total vol = 50 + 10 = 60cm3

[H+] = 1/120

pH = -lg [H+] = 2.08 (3sf)

My bad, your pH is correct.

Flying grenade SG

Alkaline hydrolysis, followed by iodoform test, is a better answer.

cannot, thats why idk how distinguish

what was the white ppt the answer key was referring to uh???

Flying grenade SG

U damn coconaden. Simple qn like this also make mistake. U wrong lah, not NJC teacher wrong. Figure out ur own mistake.

tell me la pls faster

Flying grenade SG

https://www.dropbox.com/s/q9cjxra10mbj18y/20161008_233029.jpg?dl=0

what kind of molecule is V ?

UltimaOnline SG

https://www.dropbox.com/s/q9cjxra10mbj18y/20161008_233029.jpg?dl=0

what kind of molecule is V ?

The reagents are in error. Sodium nitrite, not sodium nitrate, should be used.

Protonating O=N--O- generates O=N--O-H, which can be further protonated into O=N--OH2+ which can decompose into H2O and O=N+, an electrophile to be attacked by the amine (ie. electrophilic substitution) generate the final product of N,N-dimethylnitrosamine.

UltimaOnline SG

what was the white ppt the answer key was referring to uh???

Phenylamine

UltimaOnline SG

for this qn, conc hcl given is 0.05 M, so i calculate using nHCl = 0.05 ×10/1000

nH+ = nHCl

total vol = 50 + 10 = 60cm3

[H+] = 1/120

pH = -lg [H+] = 2.08 (3sf)

My bad, your pH is correct.

Flying grenade SG

The reagents are in error. Sodium nitrite, not sodium nitrate, should be used.

u godly sia. u pwn everyone

u should write a godlike chem textbook

Flying grenade SG

Phenylamine

phenylamine not a white solid right?

Flying grenade SG

My bad, your pH is correct.

excess 10cm3 no meh??

help pls

Flying grenade SG

or be godlike proof-reader /vetter

chem god

UltimaOnline SG

phenylamine not a white solid right?

Is phenylamine a white ppt or a yellow liquid? Depends on whether ... ... ... ... (go figure out urself, u coconaden).

Flying grenade SG

Is phenylamine a white ppt or a yellow liquid? Depends on whether ... ... ... ... (go figure out urself, u coconaden).

all 21 Singapore JCs are great

Flying grenade SG

Is YJC a good JC or a lousy JC? Depends on whether you're comparing it with MI or RJC.

Is phenylamine a white solid or a yellow liquid? Depends on whether ... ... ... ... (go figure out urself, u coconaden).

eh that soln/molecule/solid

both W and X amide both solid , pour colorless naoh in?? idk sia

help me

cocoboss/cocolover eat cocokrunch,drink coconut juice

Flying grenade SG

where my vol of HCl wrong?

rescue me pls

UltimaOnline SG

where my vol of HCl wrong?

rescue me pls

My bad, your pH is correct.

UltimaOnline SG

eh that soln/molecule/solid

both W and X amide both solid , pour colorless naoh in?? idk sia

help me cocoboss

Figure it out yourself. Think step by step what happens in the series of reactions.

Flying grenade SG

My bad, your pH is correct.

so i pwn the NJC cher for that qn

Flying grenade SG

Figure it out yourself. Think step by step what happens in the series of reactions.

alkaline hydrolysis of that two amide product all colorless

idk color of phenylamine relative to what

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