Showing working? (1 Viewer)

[ND]

I got my trial back today, and i lost many marks for not showing "adequate" working on the calculation questions. I mean, it's not like i got 2/3, he just gave me 0/3 for 2 questions, and 1/2 for another, even though i got the right answer for all of them. I did show working, i just didn't explain every little detail. In the end i finished with 83% . How much working do you need to show in the HSC?

Also, isn't redox considered a chemical reaction? I lost another two marks because i didn't have the same method the teacher used for distinguishing between metals, but he even admitted my method should work. I'm not really that pissed cos i still came first, but it would be good to know my actual raw mark result.

 

[Constip8edSkunk]

shit... and i thought my teachers were harsh

id b seriously pissed if that happened but i'd neva come first bah... the ions test omfg.... theres like shitloads 4 each 1...

as 4 working, i usually write the whateva formula, list all the known variable, write the values in, then just write the answer, 3 lines for each process, with values on the side, works at my school... should theoretically work 4 the HSC

 

[underthesun]

maybe your teacher trying to put your marks down, telling you to "study harder"?

thats what my maths teacher always does.

 

[ND]

Originally posted by Constip8edSkunk
as 4 working, i usually write the whateva formula, list all the known variable, write the values in, then just write the answer, 3 lines for each process, with values on the side, works at my school... should theoretically work 4 the HSC

Ah i didn't do all that, but i guess i will for the HSC.

maybe your teacher trying to put your marks down, telling you to "study harder"?

thats what my maths teacher always does.

Maybe... but i want a proper mark, so that i can predict my HSC raw mark.

 

[mei_ling03]

Originally posted by ND
Maybe... but i want a proper mark, so that i can predict my HSC raw mark.

what do you mean by raw mark? was it scaled??
anyways, schools vary in marking schemes so its hard to predict... have you tried asking previous students from your school what they got?

our school's like that too with teh marking.. oh well

 

[ND]

Originally posted by mei_ling03
what do you mean by raw mark? was it scaled??

Nah, what i mean is, when my teacher doesn't give me marks where i would have got them had it been a HSC marker, i can't get a proper idea of what i'm going to get. I believe that in the HSC, i would have received full marks for those calculations, and also maybe for that ion test, which would give me 90%+.

 

[mei_ling03]

actually, just remembered.. go to boardofstudies and they can the specimen paper and sample answers that'll get the top mark. compare it to yours and if its the same go complain to your teacher..

 

[sneaky pete]

Originally posted by ND
I got my trial back today, and i lost many marks for not showing "adequate" working on the calculation questions. I mean, it's not like i got 2/3, he just gave me 0/3 for 2 questions, and 1/2 for another, even though i got the right answer for all of them. I did show working, i just didn't explain every little detail.

I assume you are reffering to the CO2 calculate question on Q19 part (c) ?

I'm not sure if your school used the same markign criteria as ours, but..

+ Calculates the correct voluem of carbon dioxide produced and describes a valid assumption - 3 marks.
------------
+ Calculates the volume of carbon dioxide gas produced (using incorrect molar volume) and includes valid assumption.
OR
Calculates correct volume of carbon dioxide gas produced but does not include a valid assumption. - 2 marks
------------
+ Calculates the number of moles of carbon dioxide gas produced
OR
Calculates volume of carbon dioxide gas produced from an incorrect mole calculation
OR
Describes a valid assumption made in carrying out calculation. - 1 mark

Either way I totally agree you're entitled to additional marks.

Originally posted by ND
Also, isn't redox considered a chemical reaction?

I checked three textbooks and all seemed to agree that is:
Redox - A chemical reaction involving both reduction and Oxidation, or along those lines.
However it more or less depends on the context of your answer in relation to the question..


Hmm, I just realised that nowhere in your post did you say you completed the CSSA trial, just a trial paper :S Oh well..

 

[iambored]

Originally posted by ND
I got my trial back today, and i lost many marks for not showing "adequate" working on the calculation questions. I mean, it's not like i got 2/3, he just gave me 0/3 for 2 questions, and 1/2 for another, even though i got the right answer for all of them. I did show working, i just didn't explain every little detail. In the end i finished with 83% . How much working do you need to show in the HSC?

Also, isn't redox considered a chemical reaction? I lost another two marks because i didn't have the same method the teacher used for distinguishing between metals, but he even admitted my method should work. I'm not really that pissed cos i still came first, but it would be good to know my actual raw mark result.

u need 2 show working, but 0/3 when u had the right answer is a bit harsh! well more than a bit!
what was ur method for distinguishing between metals?

 

[Foong]

Hmmmm......... Ive got a memorised step to do working:
(equation comes here)
Mass of (enter compund with known mass or data) = _g
Molecular mass of (enter compund with known mass or data) = _g/mole
No. mole of (enter compund with known mass or data) = mass/molecular mass grams
1 mole of (enter compund with known mass or data) reacts with/creates (depends) 1 mole of (compund you want to find)
(No.mole of first compund you calculated) mole of ...........reacts with/creates (do your ratio calcultaion and put answer) mole of (second compound).
And do what ever you want with the new number of moles depending on the question. Almost all calcultaion question has this type of answer for its workin out. Its a bit messy but i hope u can understand

 

[hipsta_jess]

Originally posted by iambored
u need 2 show working, but 0/3 when u had the right answer is a bit harsh! well more than a bit!

yeah, i agree, but keep in mind that if there is no working there is no proof of your method, or even that it is your answer, for all they know you cooda totally guessed it, or looked at someone elses paper.

 

[ND]

Thanks for the replies everyone. It wasn't the CSSA, but i think some of the questions were from it.

iambored: I think it was between Fe(III) and Fe(II) sulfates, i said you could dissolve them(they are both soluble if i remember the solubility rules correctly) and set up a galvanic cell with Ag. By observing the direction of current flow, you can determine which is which. (note: my actual response was far more detailed than this).

Foong: Thanks i'll have to remember that.

hipsta_jess: I did show some working, just not *everything*.