Chem p22

[WhereAmazingHappens]

For Question 1, the element for liquid chloride was either phosphorus or silicon. For the coloured flame, it was sodium since it burns with a yellow flame in Cl2. For observations it could have been: Al glows, white solid formed/appears, Cl2 colour fades away/disappears (any 2) AlCl3 reacts with water to form Al2O3 and HCl, only Na dissolves, both Al and Si react. pH for Na was 7/neutral, for Al and Si the range of pH was 1-4 (any value in the given range) though i personally wrote 3 for Al and 2 for Si.

Chlorine burns with white flame in chlorine

Sodium burns with white flame in chlorine

 

[vishal]

35 in P12, 53 in P22 and 16 in P33.........Will these marks in chemistry fetch me an A in AS?​

 

[WhereAmazingHappens]

enthalpy is -129

im 100% sure

 

[Saad (سعد)]

But sodium burns with white flame. In the field of science white is not regarded as a color

Q1: 6 marks
Q2: Accepted i think
Q3:-129
Q4:Calculate the molar ratio between compound in the reaction
Q5:C6H8O7

Thanks a lot!

But Sodium burns in a yellow flame in chlorine. See for yourself!

Hey can u do me a favour and confirm one more thing with ur sir. Ask him that for the part in which we had to give the effect of conditons on rate of formation of methanol i wrote for temp that. = The temperature provided is low and so the r.o.f will be less bcz average kinectic energy of molecules decrease and less effective collision occurs. The temp is considered low becz for normal commercial processes the temp used is around 750K and since rx is exo low temp is preferd plz man confirm this

... Didn't they simply ask why high temperature, high pressure and a catalyst were used for the formation of methanol? I'm pretty sure I remember; that's what they asked. First there are a small paragraph at the top that told us that high pressure, high temperature and a catalyst were used industrially when making methanol, and then below that they asked to explain why these things were used.

Simply, high temperature is used as the rate of formation of methanol would increase, due to the increase in the average kinetic energy of particles. The amount of particles with energies above the activation energy increases, and there are more effective collisions between particles.

Similarly, if high pressure is used, the rate of formation of methanol would also increase as the molecules are closer together and would collide together with greater force.

And the third one was catalyst; once again, rate of formation of methanol would increase as the catalyst would provide an alternative path with lower activation energy, hence more molecules would have the necessary kinetic energy required to effectively collide and produce methanol.

o-o That's what I wrote.

 

[Saad Sarfraz]

Thanks a lot!

But Sodium burns in a yellow flame in chlorine. See for yourself!

... Didn't they simply ask why high temperature, high pressure and a catalyst were used for the formation of methanol? I'm pretty sure I remember; that's what they asked. First there are a small paragraph at the top that told us that high pressure, high temperature and a catalyst were used industrially when making methanol, and then below that they asked to explain why these things were used.

Simply, high temperature is used as the rate of formation of methanol would increase, due to the increase in the average kinetic energy of particles. The amount of particles with energies above the activation energy increases, and there are more effective collisions between particles.

Similarly, if high pressure is used, the rate of formation of methanol would also increase as the molecules are closer together and would collide together with greater force.

And the third one was catalyst; once again, rate of formation of methanol would increase as the catalyst would provide an alternative path with lower activation energy, hence more molecules would have the necessary kinetic energy required to effectively collide and produce methanol.

o-o That's what I wrote.

Okay so boy in the first paragraph they didnt write high temp. the gave 600K so i assumed it to be a low temp. caz the rx was exothermic and the temp prefferd was low

 

[Saad (سعد)]

Okay so boy in the first paragraph they didnt write high temp. the gave 600K so i assumed it to be a low temp. caz the rx was exothermic and the temp prefferd was low

... Oh.... yeah, 600 K would be like 327 degrees C... that is pretty low in terms of industrial standards.

Well, I dunno now.

 

[Saad Sarfraz]

... Oh.... yeah, 600 K would be like 327 degrees C... that is pretty low in terms of industrial standards.

Well, I dunno now.

So does that mean mine is right