Exam predictions

[chansthename]

http://vcenotes.com/forum/index.php/topic,26135.msg264613.html#msg264613

[Martoman]

I have 2 questions

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1. VCAA 2008 Sample Paper Question

Prior to the experiment, the concentration of the NaOH was experimentally determined by titrating the NaOH against a standard solution of HCl. Suppose about 10mL of the HCl were spilt on the floor during the experiment. How would you safely neutralize the spill

~ Can you say "Add diluted solution of NaOH(aq) to the spill"?

You most certainly can. BUTTTT where are you gonna pull that from.. your back pocket?

[supernatural]

im assuming there is gunna be a redox back titration
a lot of organic and reaction pathways
some dna and biofuels
and possibly a gravimetric

[m@tty]

I have 2 questions

---

1. VCAA 2008 Sample Paper Question

Prior to the experiment, the concentration of the NaOH was experimentally determined by titrating the NaOH against a standard solution of HCl. Suppose about 10mL of the HCl were spilt on the floor during the experiment. How would you safely neutralize the spill

~ Can you say "Add diluted solution of NaOH(aq) to the spill"?

You most certainly can. BUTTTT where are you gonna pull that from.. your back pocket?

You are performing a titration with it. So it should be easily accessible.

[Martoman]

nah. you don't know its concentration. So you could be putting something really basic on it and damage the floor.

[m@tty]

What did you write then?

Referring to the solutions which stonecold posted, where did sodium hydrogen carbonate come from? And sodium carbonate? lol..

What I wrote (as a joke) was: "Add two drops of methyl red, stir, slowly add NaOH stirring continuously. Cease adding NaOH when colour change is observed." lol

[Martoman]

I wrote add water.

What I wrote (as a joke) was: "Add two drops of methyl red, stir, slowly add NaOH stirring continuously. Cease adding NaOH when colour change is observed." lol

lawl you're sounding more like me every day.


Also, its standard (hahaha funny pun) to have those things around when doing acid base for spills. >.<

[m@tty]

If this is wrong then I lost two marks  :tickedoff: But I reckon the examiner would've given it to me... If only for the humour of it.

The other mark was for thinking dilution => change mole amount XD first question...

[azn_dj]

Why cant you add a weak base?
E.g. water???

[Martoman]

You can add water.

[m@tty]

Also, its standard (hahaha funny pun) to have those things around when doing acid base for spills. >.<

I never knew this. We had no such things when we performed titrations at school, though I suppose we used dilute stuff...

Why cant you add a weak base?
E.g. water???

The solutions provided by stonecold had that as an option. "further dilute the spill with a small volume of water, then wipe."

[Martoman]

Also, its standard (hahaha funny pun) to have those things around when doing acid base for spills. >.<

I never knew this. We had no such things when we performed titrations at school, though I suppose we used dilute stuff...

Why cant you add a weak base?
E.g. water???

A tiny bit of common sense will tell you to do so? diluted reduces concentration?

The solutions provided by stonecold had that as an option. "further dilute the spill with a small volume of water, then wipe."

[happyhappyland]

Also, its standard (hahaha funny pun) to have those things around when doing acid base for spills. >.<

I never knew this. We had no such things when we performed titrations at school, though I suppose we used dilute stuff...

Why cant you add a weak base?
E.g. water???

A tiny bit of common sense will tell you to do so? diluted reduces concentration?

The solutions provided by stonecold had that as an option. "further dilute the spill with a small volume of water, then wipe."

I always thought the sample papers were edited questions from the old study design. I dont think that type of question will be asked on the new study design though

[Blakhitman]

You add copious amount of water.

You don't add NaOH because then you might have the problem of having a (very) basic solution on the floor!

[m@tty]

That doesn't neutralise it. Simply spreads it all out....

Just do your titration on the floor