Predictions for Chemistry 2014 HSC? (3 Viewers)

[seventhroot]

Describe each of the layers of the atmosphere (4 marks)

true

 

[enigma_1]

When there are 2 possible molecular formulae for the same isomer, the one with least sum of numbers take preference

but 1+3 = 4

and 2+4= 6 so should it be the first?

 

[enigma_1]

true

gg

 

[QZP]

but 1+3 = 4

and 2+4= 6 so should it be the first?

Count the other ones too

 

[SuchSmallHands]

wait sorry just to confirm, why cant you start off with 1,3-dibromo etc? How do you get the 2,4 dibromo thing?

Name in whatever direction gives the lowest overall numbers. Naming it from right to left means that if you add all the numbers together at the end you get the lowest net number

This could also be called something along the lines of 2,4-dibromo-2-chlorofluoromethylbutane, just in case that comes up in a multiple choice and the other way isn't an option (that name could be wrong though, I've never done one like that before).

 

[seventhroot]

Count the other ones too

gg

.

 

[QZP]

Also I shouldn't have said molecular formula. I forgot what form this is: e.g. bromoalkene?

 

[SuchSmallHands]

but 1+3 = 4

and 2+4= 6 so should it be the first?

There's also the chloro, fluoro and methyl things to include

 

[enigma_1]

Count the other ones too

Name in whatever direction gives the lowest overall numbers. Naming it from right to left means that if you add all the numbers together at the end you get the lowest net number

This could also be called something along the lines of 2,4-dibromo-2-chlorofluoromethylbutane, just in case that comes up in a multiple choice and the other way isn't an option (that name could be wrong though, I've never done one like that before).

Also I shouldn't have said molecular formula. I forgot what form this is: e.g. bromoalkene?

There's also the chloro, fluoro and methyl things to include

omg guys thanks so much I never knew this and no wonder I always get them wrong in MC :/

@QZP I think it's haloalkane

 

[zhertec]

omg guys thanks so much I never knew this and no wonder I always get them wrong in MC :/

@QZP I think it's haloalkene

ftfy

 

[SuchSmallHands]

ftfy

Not sure if srs

 

[QZP]

SSH what are you plans for today? Taking it lightly? I'm just going through responses in my head and then checking with marking guidelines. Nearing the end of the day I'm going to start memorising my notes

 

[SuchSmallHands]

SSH what are you plans for today? Taking it lightly? I'm just going through responses in my head and then checking with marking guidelines. Nearing the end of the day I'm going to start memorising my notes

Something similar, past paper questions and then going over notes later on tonight. Hopefully I'll wake up early tomorrow and review as well. I've also lost my calculator and desperately need to find it before tomorrow, so I'll have to fit that in somewhere

 

[zhertec]

Something similar, past paper questions and then going over notes later on tonight. Hopefully I'll wake up early tomorrow and review as well. I've also lost my calculator and desperately need to find it before tomorrow, so I'll have to fit that in somewhere

Still on that quest to find the holy calculator? lol

I haven't even finished all HSC past papers QQ

 

[faisalabdul16]

Describe each of the layers of the atmosphere (4 marks)

This is an ugly question.

The troposphere is within the sea level to 10km range. Here temperatures are at its lowest in comparison to the other spheres and this is where nitrogen is the predominant gas, making up 78% of the atmosphere, followed by oxygen (20%) and then argon. The troposphere is where pollutant gases may be formed through human activity such as ozone which is dangerous as it is an irritant, however in the stratosphere (second atmospheric layer) ozone is of a benefcial advantage to us humans as it forms a barrier, preventing strong UV rays from entering into the troposphere and causing cataracts along with an increase in skin cancer. Stratosphere is approximately 15-50km above sea level. The mesosphere is 50-85km where there is barely any gases but has a few gas particles that would not exist in the previous spheres, and the temperature is higher than that of the stratosphere and troposphere because here there are strong UV rays and no ozone to shield it. Thermosphere as its name suggests is the hottest 85km +, barely any gases or particles present due to the heat.

 

[Queenroot]

omg guys thanks so much I never knew this and no wonder I always get them wrong in MC :/

@QZP I think it's haloalkane

Start from the side which has the most electronegative halide.
In this case its IUPAC would be chloro-2,4-dibromofluoro-2-methylbutane

 

[faisalabdul16]

Start from the side which has the most electronegative halide.
In this case its IUPAC would be chloro-2,4-dibromofluoro-2-methylbutane

You don't do electronegative, you do alphabetical.

 

[Queenroot]

You don't do electronegative, you do alphabetical.

I meant to know which side to start naming from. Then obviously when you name it you have to write it in alphabetical.

 

[enigma_1]

This is an ugly question.

The troposphere is within the sea level to 10km range. Here temperatures are at its lowest in comparison to the other spheres and this is where nitrogen is the predominant gas, making up 78% of the atmosphere, followed by oxygen (20%) and then argon B] temperature decreases with altitude and there is presence of convection currents which mix the gases of the troposphere including N2, O2, H2O, CO2, Ar gases)[[/B]. The troposphere is where pollutant gases may be formed through human activity such as ozone which is dangerous as it is an irritant, however in the stratosphere (second atmospheric layer) ozone is of a benefcial advantage to us humans as it forms a barrier, preventing strong UV rays UV-B AND UV-C from entering into the troposphere and causing cataracts along with an increase in skin cancer whilst UV-A is let through which is beneficial for photosyntheisis and promotes formation of vitamin D on skin. Stratosphere is approximately 15-50km above sea level and temperature increases with altitude and there is less vertical mixing of gases here whilst there is presence of some convection currents, hence pollutants which enter the stratosphere remain there for a long time, because the gases don't really mix much. The mesosphere is 50-85km where there is barely any gases but has a few gas particles that would not exist in the previous spheres, and the temperature is higher than that of the isn't the temperature really low here? It's -100 degrees Celsius and temperature decreases with altitudestratosphere and troposphere because here there are strong UV rays and no ozone to shield it. Thermosphere as its name suggests is the hottest 85km +, barely any gases or particles present due to the heat temperature 1700 degrees celsius. and the ionosphere also exists somewhere here where there is presence of gaseous ions of molecules such as O2+, O+, NO+ and temperature increases with altitude and the air is also really thin here

hahahha intended to be a yucky question, soz

 

[Queenroot]

no even that, they changed it Adrita

though seriously because there is so much discrepancy as to how it is taught across schools, I've heard that they give compounds where its possible to get the same name with either method

Okay next question: Compare the processes of thermal and catalytic cracking (4 marks)

Oh wtf, why is the HSC so fucked. I am talking about IUPAC naming.