Question Chain Thread !!! (2 Viewers)

[JasonNg1025]

Ok *braces myself*
*Gets a better idea and steals Azreil's whip*

Gosh danz90, Azreil still hasn't noticed, I think, that I've been editing her name in all the quotes from page 33 xD

 

[danz90]

LOL.

I think I better go and do some light reading of notes.

I'll be back soon.

 

[:::a:::]

HEY, re: Batteries, what are and how many types do you need to know, and what specifically do you need to know about it apart from its construction and half-reactions?

 

[JasonNg1025]

The dot point says it all:

"Gather and present information on the structure and chemistry of a dry cell or lead-acid cell and evaluate it in comparison to one of the following:

-Button Cell
-Fuel Cell
-Vanadium redox cell
-Lithium Cell
-Liquid junction photovoltaic cell (e.g. the Gratzel Cell)

in terms of

-Chemistry
-Cost and practicality
-Impact on society
-Environmental impact"

Know either the dry cell or lead-acid cell in full detail... it's been asked on before

 

[hoochiscrazy]

can someone post a neutralisation reaction question?

 

[:::a:::]

The dot point says it all:

"Gather and present information on the structure and chemistry of a dry cell or lead-acid cell and evaluate it in comparison to one of the following:

-Button Cell
-Fuel Cell
-Vanadium redox cell
-Lithium Cell
-Liquid junction photovoltaic cell (e.g. the Gratzel Cell)

in terms of

-Chemistry
-Cost and practicality
-Impact on society
-Environmental impact"

Know either the dry cell or lead-acid cell in full detail... it's been asked on before

cheers man. which did you study (aka which was the easiest to remember?) im thinking ill do dry cell so which is a good battery to compare it with?

 

[JasonNg1025]

NaOH_(aq) + HCl_(aq) --> NaCl_(aq) + H₂O_(l)

 

[JasonNg1025]

cheers man. which did you study (aka which was the easiest to remember?) im thinking ill do dry cell so which is a good battery to compare it with?

I do dry cell and mercury oxide button cell. Some like the silver oxide button cell, they're very similar. If you're going to study it now, definitely do a button cell as it's easy and you should be able to get it done by tomorrow

 

[Azreil]

YOU STOLE MY WHIP! D:

Calculate the pH of a substance when 30mL 0.2M NaOH is mixed with 40mL 0.1M H2SO4.

 

[JasonNg1025]

Yiss yiss

Question - who were Bronsted and Lowry?

 

[SkimDawg]

YOU STOLE MY WHIP! D:

Calculate the pH of a substance when 30mL 0.2M NaOH is mixed with 40mL 0.1M H2SO4.

Is it pH = 1.544.. or something similar? I need to get these damn questions right before tomorrow lol

 

[nandayo]

Is it pH = 1.544.. or something similar? I need to get these damn questions right before tomorrow lol

Think you've calculated the pOH. Pretty sure you take that from 14 and get the final pH which is basic at 12.46, because H2SO4 is the limiting reagent and there are excess OH ions.

 

[aussiechick007]

Can someone explain this method to me:

Calculate the molar heat of combustion of ethanol

delta H = -m C delta t

m = 300 g (water)
C = 4.18 x10^3 (J/kg)
t = 20.5 degrees

it's from a past hsc and yes, i am stupid.

erm, dont we need to know the mass of ethanol that was burnt?

 

[hoochiscrazy]

YOU STOLE MY WHIP! D:

Calculate the pH of a substance when 30mL 0.2M NaOH is mixed with 40mL 0.1M H2SO4.

I got pH=1.54 (2.S.F)

 

[eddy11]

describe a test to quantitatively measure turbdity

 

[aussiechick007]

for the pH question, i got ph = 1.244 ??

 

[aussiechick007]

describe a test to quantitatively measure turbdity

pass light through a water sample and measure the intensity of the light scattered at 90o from the water. It is measured in nephelometic turbidity units, NTU.

(not a very good answer i know...)

Discuss factors that must be considered when using neutralisation reactions to safely minimise damage in chemical spills.

 

[JasonNg1025]

describe a test to quantitatively measure turbdity

You could
Get a piece of white paper, draw a black cross on it. Place this under a calibrated cylinder, and fill with water until the cross disappears. Read the calibrations to determine the amount.

 

[aussiechick007]

^ thats not very accurate, lol

 

[:::a:::]

You could
Get a piece of white paper, draw a black cross on it. Place this under a calibrated cylinder, and fill with water until the cross disappears. Read the calibrations to determine the amount.

similar to a secchi disk, no?