Chemistry: Post your doubts here!

[The Sarcastic Retard]

Apply the knowledge that C can form 4 bonds, O can 2 and H can 1 it will look like this :

Metanoia m i correct? why does ms says we have to draw two diagrams? :/ and y there is no 2 oxygen attached in 1st diagram in ms

 

[Metanoia]

Metanoia m i correct? why does ms says we have to draw two diagrams? :/ and y there is no 2 oxygen attached in 1st diagram in ms

I think to be safe, I would want to see the rest of the original question to see the context.

 

[The Sarcastic Retard]

I think to be safe, I would want to see the rest of the original question to see the context.

http://onlineexamhelp.com/wp-content/uploads/2014/02/9701_w13_qp_22.pdf
Q4

 

[Metanoia]

Metanoia m i correct? why does ms says we have to draw two diagrams? :/ and y there is no 2 oxygen attached in 1st diagram in ms

Drawing the 2nd diagram will get you the two marks.

If students only managed to draw the first diagram (incomplete) , they will get 1 out of the max 2 marks.

 

[The Sarcastic Retard]

Drawing the 2nd diagram will get you the two marks.

If students only managed to draw the first diagram (incomplete) , they will get 1 out of the max 2 marks.

Hey Electron affinity is in As level?
What if I draw like this :

 

[Metanoia]

Hey Electron affinity is in As level?
What if I draw like this :

Your diagram is fine. Its the same as the marking scheme.

 

[The Sarcastic Retard]

Your diagram is fine. Its the same as the marking scheme.

The first one is not same, I have drawn two Oxygen atoms as well which is not der in ms

 

[Metanoia]

The first one is not same, I have drawn two Oxygen atoms as well which is not der in ms

Erm, as I have explained. The 1st diagram is the incomplete answer. Students who produced the 1st diagram will only get 1 mark.

Students who produced the 2nd diagram gets 2 marks.

 

[The Sarcastic Retard]

Erm, as I have explained. The 1st diagram is the incomplete answer. Students who produced the 1st diagram will only get 1 mark.

Students who produced the 2nd diagram gets 2 marks.

I see... I thought 1 mark for the 1st dia and 2 marks for 2nd dia and so total 3 marks... *Phew* ty

 

[Studydayandnight]

T reacting with an excess of Na

NaO2CCH(ONa)CH2CO2Na ----> Over here Na, replaces the H in the alcohol group.

U reacting with an excess of Na2CO3

NaO2CCH(OH)CH(OH)CO2Na ---> Over here it doesn't. :s Why?

 

[The Sarcastic Retard]

T reacting with an excess of Na

NaO2CCH(ONa)CH2CO2Na ----> Over here Na, replaces the H in the alcohol group.

U reacting with an excess of Na2CO3

NaO2CCH(OH)CH(OH)CO2Na ---> Over here it doesn't. :s Why?

Are both question same?
What do u want the Mr of S , T and U or something else u wrote?

 

[Metanoia]

T reacting with an excess of Na

NaO2CCH(ONa)CH2CO2Na ----> Over here Na, replaces the H in the alcohol group.

U reacting with an excess of Na2CO3

NaO2CCH(OH)CH(OH)CO2Na ---> Over here it doesn't. :s Why?

Sodium metals react with OH, COOH
Sodium hydroxide react with COOH
sodium carbonates react with COOH.

 

[The Sarcastic Retard]

T reacting with an excess of Na

NaO2CCH(ONa)CH2CO2Na ----> Over here Na, replaces the H in the alcohol group.

U reacting with an excess of Na2CO3

NaO2CCH(OH)CH(OH)CO2Na ---> Over here it doesn't. :s Why?

Mr of S = 1 + 32 + 12 + 12 +1 + 12 + 1 + 12 + 32 + 1 = 116
Same way T = 134 And U = 150

 

[Studydayandnight]

Mr of S = 1 + 32 + 12 + 12 +1 + 12 + 1 + 12 + 32 + 1 = 116
Same way T = 134 And U = 150

Lol, that wasn't my doubt

It was why Na2CO3, didn't react with OH, turns out it just doesn't

Thanks though.

 

[Laila39]

Can someone please give me a list of all the flames we need to know? I cant find the appropriate ones anywhere! Please thanks guyss
-AS inorganic

 

[qwertypoiu]

Can someone please give me a list of all the flames we need to know? I cant find the appropriate ones anywhere! Please thanks guyss
-AS inorganic

Reaction with oxygen :
Sodium - golden yellow flame
Magnesium - sparkling bright flame (no colour)
Aluminum - bright flame (no color)
Phosphorus - yellow flame
Sulfur - pale blue flame

 

[Sarosh Jameel]

PLZ HELP ME WITH THIS ONE !

 

[psychiatrist]

Q6. From the relative abundance chart. Ratio of Isotope-10 : Isotope - 11 is 1:4

Q17. I saw the wrong question and explained for Q14.
Use your data booklet and locate the elements that represent the four options. Fill them in here before I explain further.
A.
B.
C.
D.

Q18. Again, us your data booklet write down the 1st, 2nd and 3rd IE of four options. Fill them in here before I explain further.
C
N
F
Na

Q27. From your understanding, how many protons, electrons and neutrons does Tc have?

Q6 : This is not taught in our school... 1/5 or 4/5 why only by 5?

Q17 :
A: Mg
B: Al
C: Si
D : P

Q18 :
C : 1090 2350 4610
N : 1400 2860 4590
F : 1680 3370 6040
Na : 494 4560 6940

Q27 :
p = 43 e = 43 n = 56

 

[ali_jaliawala]

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[ali_jaliawala]

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Please help us in spreading the page so that maximum students can avail this opportunity!
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