Chemistry: Post your doubts here!

[Metanoia]

Aoa, can someone help plz

In your working, you should have wrongly used 100 as the dominator rather than 10.

 

[yousef]

Why we dont count the two blue ones > they are tertiary?

 

[Aly Emran]

These too....plllzzz

 

[awesomaholic101]

Why we dont count the two blue ones > they are tertiary?

You can only count one Carbon from a single C=C bond ... as one ketone is formed from one C=C bond.

 

[Aly Emran]

 

[awesomaholic101]

View attachment 54852

Plz help

D rite?

 

[FranticAmaze]

D rite?

Yupp

 

[Studydayandnight]

Given the following enthalpy changes,
I2(g) + 3Cl2(g) → 2ICl3(s) ∆Ho = –214kJ mol–1
I2(s) → I2(g) ∆Ho = +38 kJ mol–1
What is the standard enthalpy change of formation of iodine trichloride, ICl3(s)?

A +176kJ mol–1
B –88kJ mol–1
C –176kJ mol–1
D –214kJ mol–1

Correct answer is B.

 

[Studydayandnight]

How is this C?

HELPPPP

 

[Studydayandnight]

The Haber process for the manufacture of ammonia is represented by the following equation.
N2(g) + 3H2(g) 2NH3(g) ∆H = –92kJ mol–1
Which statement is correct about this reaction when the temperature is increased?

A Both forward and backward rates increase.
B The backward rate only increases.
C The forward rate only increases.
D There is no effect on the backward or forward rate.

Why is the correct answer A? The reaction in exothermic so by increasing the temperature, won't the backward reaction increase only?

 

[Studydayandnight]

Use of the Data Booklet is relevant to this question.
2.920 g of a Group II metal, X, reacts with an excess of chlorine to form 5.287 g of a compound with formula XCl2.
What is metal X?
A barium
B calcium
C magnesium
D strontium

Correct answer is D.

 

[The Sarcastic Retard]

The same quetions are repeated in the thread..

 

[My Name]

The same quetions are repeated in the thread..

If you can find them,post the links...

 

[awesomaholic101]

Yupp

 

[princess Anu]

The Haber process for the manufacture of ammonia is represented by the following equation.
N2(g) + 3H2(g) 2NH3(g) ∆H = –92kJ mol–1
Which statement is correct about this reaction when the temperature is increased?

A Both forward and backward rates increase.
B The backward rate only increases.
C The forward rate only increases.
D There is no effect on the backward or forward rate.

Why is the correct answer A? The reaction in exothermic so by increasing the temperature, won't the backward reaction increase only?

When temp is increased, rate increases for both forward & backward. When they ask you for yield, then you can say yield of Nh3 will decrease.

 

[asadalam]

Which mixtures, on heating, produce the gas ND3?
[D = H 2
1 , an isotope of hydrogen]
1 CaO(s) and ND4Cl(s)
2 CH3CN and NaOD in D2O
3 NDH3Cl and NaOD in D2O

So D is like H so we can suppose NDH3Cl as NH4Cl so wouldnt reaction 3 also liberate ammonia?The Ms says only 1,2 are correct.

 

[nehaoscar]

I think you have asked similar questions on this? This question is on intermolecular forces of attraction. HCl has the strongest intermolecular attraction (PD-PD) compared to the other options (VDW).




ammonium salt + base --> salt + water + ammonia

It is "bad" because, the nitrogen nutrient which is meant to be taken in by the plants is lost to the surroundings as ammonia gas.

Thankyou! And yes I always keep thinking of the bond energies...

 

[princess Anu]

These too....plllzzz
View attachment 54857 View attachment 54858 View attachment 54860 View attachment 54861 View attachment 54862

last que: n^2= no of cis trans isomers .where n is the no of double bonds.
2nd last Que : if you find the oxidation no of Ag in the ion (on the product side & on reactant side)it will be +1.. which means it stays the same.. so the rest of the options are wrong

 

[awesomaholic101]

Which mixtures, on heating, produce the gas ND3?
[D = H 2
1 , an isotope of hydrogen]
1 CaO(s) and ND4Cl(s)
2 CH3CN and NaOD in D2O
3 NDH3Cl and NaOD in D2O

So D is like H so we can suppose NDH3Cl as NH4Cl so wouldnt reaction 3 also liberate ammonia?The Ms says only 1,2 are correct.

The 3rd reaction doesn't involve D2O ... it is just the reaction between (Ammonium salt) NDH3Cl + (alkali) NaOD ... so we have only 2 D atoms now, but we actually need 3 D atoms to produce ND3 ...
so probably sth like ND2H or sth is produced instead, but that doesn't matter.

 

[muhammadali233]

Good luck everyone!