Predictions for Chemistry 2014 HSC? (1 Viewer)

[Jim Moriarty]

I think we'll get a good calculation question this year.

Try this one:

The solubility of highly soluble, thermally unstable salts such as ammonium chloride may be determined by back titration.

In one experiment a 5.00 mL saturated solution of ammonium chloride, NH4Cl, at 20oC,
was diluted with distilled water to 250.0 mL in a standard flask.

A 20.0 mL aliquot of this solution was added to 10.0 mL of 0.400 M NaOH solution.
The solution was heated to drive off the ammonia formed by this reaction.

When the flask had cooled, the excess hydroxide ions were neutralised by 14.7 mL of 0.125 M HCl solution. The molar mass of ammonium chloride is 53.5 g/mol.

(i) Write an equation for the neutralisation reaction.
(ii) Determine the amount, in mole, of NaOH that was originally added to the ammonium chloride solution.
(iii) Determine the amount, in mole, of ammonium chloride in the 20.0 mL aliquot.
(iv) Calculate the amount, in mole, of ammonium chloride in 5.00 mL of the saturated solution.
(v) Calculate the solubility, in g/L, of ammonium chloride in water at 20oC.

7 marker, 1 + 1 + 2 + 1 + 2

This was from the 2012 VCE Chemistry Paper for those interested.

 

[faisalabdul16]

My question is:

Name a metal on the periodic table that would be used for the manufacture of aircraft.


Why?




(2 marks)

Helium.

 

[Speed6]

Helium.

Correct.











Not.

 

[Futuremedstudent]

what is the hardest substance? (0.5 marks)

 

[enigma_1]

I am the shitstorm

engima bring it brahh

hahahh gonna maintain peace before hsc

My question is:

Name a metal on the periodic table that would be used for the manufacture of aircraft.


Why?




(2 marks)

iirc prelim question? Sorry I failed + forgot prelim chem.

Clearly i was joking

I never know when you're joking. Just dun make mean jokes, k thx

 

[mreditor16]

I have a bad feeling someone is going to get infracted or banned due to this derailing. Be careful guys :/

 

[Futuremedstudent]

My question is:

Name a metal on the periodic table that would be used for the manufacture of aircraft.


Why?




(2 marks)

aluminium, high boiling and melting point

 

[Queenroot]

what is the hardest substance? (0.5 marks)

Diamonds

Jokes it's SR's dick

 

[SuchSmallHands]

Assess the use of ethene as a raw material (5 marks)

 

[seventhroot]

Diamonds

Jokes it's SR's dick

seen

huehuehue

inb4Adrita

 

[Queenroot]

seen

huehuehue

inb4Adrita

smh, you ruin your chance everytime with that autistic reply

 

[faisalabdul16]

I think we'll get a good calculation question this year.

Try this one:

The solubility of highly soluble, thermally unstable salts such as ammonium chloride may be determined by back titration.

In one experiment a 5.00 mL saturated solution of ammonium chloride, NH4Cl, at 20oC,
was diluted with distilled water to 250.0 mL in a standard flask.

A 20.0 mL aliquot of this solution was added to 10.0 mL of 0.400 M NaOH solution.
The solution was heated to drive off the ammonia formed by this reaction.

When the flask had cooled, the excess hydroxide ions were neutralised by 14.7 mL of 0.125 M HCl solution. The molar mass of ammonium chloride is 53.5 g/mol.

(i) Write an equation for the neutralisation reaction.
(ii) Determine the amount, in mole, of NaOH that was originally added to the ammonium chloride solution.
(iii) Determine the amount, in mole, of ammonium chloride in the 20.0 mL aliquot.
(iv) Calculate the amount, in mole, of ammonium chloride in 5.00 mL of the saturated solution.
(v) Calculate the solubility, in g/L, of ammonium chloride in water at 20oC.

7 marker, 1 + 1 + 2 + 1 + 2

This was from the 2012 VCE Chemistry Paper for those interested.

 

[seventhroot]

smh, you ruin your chance everytime with that autistic reply

tbh; you said there was never a chance so yeah....

 

[faisalabdul16]

Hold on, i believe my second is wrong!!

 

[Queenroot]

tbh; you said there was never a chance so yeah....

das true lel

 

[seventhroot]

das true lel

:'(

 

[Queenroot]

:'(

but you noice <3

 

[seventhroot]

but you noice <3

k

 

[Hi there444]

Hold on, i believe my second is wrong!!

 

[faisalabdul16]

I think we'll get a good calculation question this year.

Try this one:

The solubility of highly soluble, thermally unstable salts such as ammonium chloride may be determined by back titration.

In one experiment a 5.00 mL saturated solution of ammonium chloride, NH4Cl, at 20oC,
was diluted with distilled water to 250.0 mL in a standard flask.

A 20.0 mL aliquot of this solution was added to 10.0 mL of 0.400 M NaOH solution.
The solution was heated to drive off the ammonia formed by this reaction.

When the flask had cooled, the excess hydroxide ions were neutralised by 14.7 mL of 0.125 M HCl solution. The molar mass of ammonium chloride is 53.5 g/mol.

(i) Write an equation for the neutralisation reaction.
(ii) Determine the amount, in mole, of NaOH that was originally added to the ammonium chloride solution.
(iii) Determine the amount, in mole, of ammonium chloride in the 20.0 mL aliquot.
(iv) Calculate the amount, in mole, of ammonium chloride in 5.00 mL of the saturated solution.
(v) Calculate the solubility, in g/L, of ammonium chloride in water at 20oC.

7 marker, 1 + 1 + 2 + 1 + 2

This was from the 2012 VCE Chemistry Paper for those interested.

Are you sure iii and iv is mol? I have this feeling its concentration.