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Chemistry: Post your doubts here!

Student12

Student12

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Ammonium nitrate, NH4NO3, can decompose explosively when heated.
NH4NO3 → N2O + 2H2O
What are the changes in the oxidation numbers of the two nitrogen atoms in NH4NO3 when this
reaction proceeds?
A –2, –4 B +2, +6 C +4, –6 D +4, –4

The answer is D !? someone please do it for me ? i didnt get it! :/
 
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leosco1995

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Student12 said:
Ammonium nitrate, NH4NO3, can decompose explosively when heated.
NH4NO3 → N2O + 2H2O
What are the changes in the oxidation numbers of the two nitrogen atoms in NH4NO3 when this
reaction proceeds?
A –2, –4 B +2, +6 C +4, –6 D +4, –4

The answer is D !? someone please do it for me ? i didnt get it! :/
Click to expand...
Figure out the oxidation numbers in both N atoms in NH4NO3 and compare it with the oxidation number of N in N2O. Like so:

You split up NH4NO3 into the NH4+ and NO3- ions.

In NH4+, the charge on Nitrogen is 1 - 4 = -3.
In NO3-, the charge on Nitrogen is -1 + 6 = +5.

And in N2O, the charge on nitrogen is 2/2 = +1.

And the changes in these are +4 and -4 respectively, meaning D is right.
 
Student12

Student12

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hmlahori

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Can someone please explain these paper 1 questions? This is the third time im posting them!​
​
Q6 How is hydrogen more ideal than nitrogen? ​
Q11 How should this question be solved?​
​
Q21 How does the compound have 5 double bonds. I counted 6(one in the side chain and 5 in the cyclohexene ring due to presense of just one hydrogen in it.)​
 
G

geek101

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hmlahori said:
Can someone please explain these paper 1 questions? This is the third time im posting them!​
​
Q6 How is hydrogen more ideal than nitrogen? ​
Q11 How should this question be solved?​
​
Q21 How does the compound have 5 double bonds. I counted 6(one in the side chain and 5 in the cyclohexene ring due to presense of just one hydrogen in it.)​
Click to expand...

Q6) what i think is because, Nitrogen's molecule has more no. of electrons than the hydrogen molecule, therefore it's gonna have stronger vanderwaals forces than H, so as the intermolecular forces increase the gas is more likely to deviate from ideal gas behaviour.

Q11) ok, here just use algebra. we know that the no of moles of reactants initially is 1.
The mole ratio of the reactants and products is 1:1
therefore at equilibrium lets assume that x no of moles reacted. so now the moles of ethanol and ethanoic acid are 1-x and 1-x. on the products side since x moles reacted, to the moles of water and ethyl ethanoate are x, and x.
Now put it into the Kc equation:
(1-x)^2 ÷ x^2 = 4
square root both sides to make it easier.
now (1-x) ÷ x = 4
solve it ull get 2/3.

Q21) firstly is is cis form so its either A or C. haha thats it. i dont know, this is what the examiner report says:
''Presumably many of the former group did not appreciate that
the formation of a ring system has the same effect on the C:H ratio of the molecular formula as does a
double bond.''
 
Scafalon40

Scafalon40

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smzimran said:
No offense brother but..
I think they did the right thing, its not their responsibility to spend time deciding whether you were serious or joking!
They just have to make sure no body goes against the rule!
Click to expand...
None taken.
You are right friend, they did do the right thing, if you say so.
Anyway, it was funny while it lasted:LOL:
 
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geek101

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iKhaled said:
hey guys..i need help in question 1 in may/june p1​
​
​
this q drove me crazy Oo​
Click to expand...

this is what i think, first calculate the moles of H2 (molecule) 1/2 = 0.5 moles
now the no. of moles of the atoms is 0.5 x 2 = 1
the no of atoms = no. of moles x 6.02x10^23
which is 1x 6.02x10^23 = 6.02x10^23
now from the options the only one with the no. of moles = 1 is C Neon. 20/20 = 1
 
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