Chemistry Predictions/Thoughts (9 Viewers)

[nowomansland]

They likely won't specify LDPE and HDPE, but they might say any of the polymers mentioned in the syllabus. Or they might give an unseen polymer and ask to give possible uses and stuff.

it was specified in our trials so i feel like it is possible, its best to know the diffs anyway

 

[coolcat6778]

Wtf is wrong with this school? Why the fuck are they deducted 10 marks (it's 10 marks, not 5) for wrong sig figs?

Sig figs is legit a year 7 math topic . testing it once is okay, testing it as if the entire exam is a year 7 math exam is just wrong

 

[nowomansland]

wait guys for soaps and detergents what soecifically do we gotta know

soaps are a surfactant: carboxylate ion polar hydrophilic head, long non-polar hydrocarbon hydrophobic tail
oil + soap + water = micelle
soap + minerals in hard water --> scum
detergent is good bc no scum
detergent types: anionic, cationic, non-ionic
saponification: triglyceride (fats) + NaOH --> soap molecule + glycerol

 

[eternallyboreduser]

soaps are a surfactant: carboxylate ion polar hydrophilic head, long non-polar hydrocarbon hydrophobic tail
oil + soap + water = micelle
soap + minerals in hard water --> scum
detergent is good bc no scum
detergent types: anionic, cationic, non-ionic
saponification: triglyceride (fats) + NaOH --> soap molecule + glycerol

do we gotta know the strucutr for the detergents

 

[nowomansland]

do we gotta know the strucutr for the detergents

detergent structure is basically the same except the heads but idk what type of question they would ask abt it? maybe in the mcqs?

 

[anonymoushehe]

detergent structure is basically the same except the heads but idk what type of question they would ask abt it? maybe in the mcqs?

wait we need to know about saponification? thought we just need to know properties of polymers which says it on syllabus?

 

[thatnerdyhylian]

wait we need to know about saponification? thought we just need to know properties of polymers which says it on syllabus?

Syllabus says "investigate the structure and action of soaps and detergents"

 

[anonymoushehe]

Syllabus says "investigate the structure and action of soaps and detergents"

so wouldnt it just be know the general strucrture of it not the process of how its made

 

[thatnerdyhylian]

so wouldnt it just be know the general strucrture of it not the process of how its made

I think so yeah

 

[nowomansland]

so wouldnt it just be know the general strucrture of it not the process of how its made

we learnt abt it in class & its in the textbook so
idt they would ask us to explain the process or anything but its still good to know abt it if it came up in the mcqs

 

[Geniusly]

Syllabus says "investigate the structure and action of soaps and detergents"

Saponification is old syllabus like 2018 and previous. You can still know it if that helps, but you shouldn't be asked a question about the process of it. They ask questions mainly about the process of soap as a cleaning agent and how it works compared to detergents in hard water.

 

[lawfirm]

what was the hardest hsc for this syllabus

 

[HappyTheSkibidi]

what was the hardest hsc for this syllabus

2021

 

[nowomansland]

do we need to know all the processes from chemical synthesis topic

 

[tsswhzl]

wait guys why do bigger compounds release more energy when combustrf again

they have more bonds

 

[C2H6O]

wait guys why do bigger compounds release more energy when combustrf again

a more accurate explanation is that they form more molecules of products like co2 and h2o per molecule combusted and its the formation of new bonds which releases energy

 

[lolcti]

How to memorise whole syllabus in one day no glue no borax?

 

[thatnerdyhylian]

wait guys why do bigger compounds release more energy when combustrf again

Also see chem.libretexts.org/Bookshelves/Introductory_Chemistry/The_Basics_of_General_Organic_and_Biological_Chemistry_(Ball_et_al.)/07:_Energy_and_Chemical_Processes/7.04:_Bond_Energies_and_Chemical_Reactions

 

[sakinluvo]

is this year gonna be like 2021 paper or more 2023 easy style

 

[WERTYQDUNE]

I know i'm gonna fail this test horribly, are there any interesting things i can do with a Casio FX82AU Plus II while waiting for the exam to finish? (on trials I 'finished' an 1.5 hours early ((cause could only answer half the questions))