Ask me for chemistry help! (1 Viewer)

[MagnificentOne]

Tell me what you want to know ; )
shoot your q's right here guys
ill get back to you ASAP

 

[littlej123]

whats in the exam hahaha,

 

[MagnificentOne]

=]

 

[MagnificentOne]

shoot em up!

 

[littlej123]

thats my question. whats in the exam??

 

[MagnificentOne]

Assess the use of ethanol as an alternative fuel.

 

[kittyful]

Should we know the formula for photodisasociation ? if so what is it ?

 

[MagnificentOne]

Nope, that formula is not needed.

 

[zxreth]

Assess the use of ethanol as an alternative fuel.

are you serious?

 

[kittyful]

what is the scale that the -log[H+] scale goes up by?

 

[kittyful]

If you wash a burette with water before titration, what effect will it have on the results ?

 

[Dylanamali]

what is the scale that the -log[H+] scale goes up by?

what is photodisassociation? never heard that term in chemistry - unless its apart of an option topic?

pH = - log[H+] .. a change in one pH correlates to a 10fold change in H+ concentration.
E.g. juice with say a pH of 5 differs to disilled water with a pH of 7 by 100 times H+ concentration. (10x10)

 

[MagnificentOne]

pH goes up 1 = Hydrogen ion conc. decreases by 10
Alternatively. . .
pH goes down 1 = Hydrogen ion conc. increases by 10

 

[kittyful]

what is photodisassociation? never heard that term in chemistry - unless its apart of an option topic?

pH = - log[H+] .. a change in one pH correlates to a 10fold change in H+ concentration.
E.g. juice with say a pH of 5 differs to disilled water with a pH of 7 by 100 times H+ concentration. (10x10)

Photodisassociation is in Module 3 Chemical montioring ... its about the Ozone

 

[Dylanamali]

If you wash a burette with water before titration, what effect will it have on the results ?

If you wash a burette with water before the titration - the titre will be more dilute then anticipated. That is, because of remaining water droplets in the burette when you pour in your standard solution the concentration will be slightly diluted. Because of this, when you titrate it against the unknown, you will have to ADD MORE of the solution to neutralise the unknown. BECAUSE of this, you will think the unknown is MORE CONC then it really is, as it needed more titre to be neutralised. That is why we rinse the burette with the solution it contains...

If it ends with 'ette' rinse it with the solution its going to contain, if it doesnt rinse it with distilled water.

 

[MagnificentOne]

Photodisassociation is in Module 3 Chemical montioring ... its about the Ozone

That is not needed!

 

[kittyful]

If you wash a burette with water before the titration - the titre will be more dilute then anticipated. That is, because of remaining water droplets in the burette when you pour in your standard solution the concentration will be slightly diluted. Because of this, when you titrate it against the unknown, you will have to ADD MORE of the solution to neutralise the unknown. BECAUSE of this, you will think the unknown is MORE CONC then it really is, as it needed more titre to be neutralised. That is why we rinse the burette with the solution it contains...


If it ends with 'ette' rinse it with the solution its going to contain, if it doesnt rinse it with distilled water.

So does that mean that the end conc. will be higher than expected ?

 

[MagnificentOne]

If you wash a burette with water before the titration - the titre will be more dilute then anticipated. That is, because of remaining water droplets in the burette when you pour in your standard solution the concentration will be slightly diluted. Because of this, when you titrate it against the unknown, you will have to ADD MORE of the solution to neutralise the unknown. BECAUSE of this, you will think the unknown is MORE CONC then it really is, as it needed more titre to be neutralised. That is why we rinse the burette with the solution it contains...

If it ends with 'ette' rinse it with the solution its going to contain, if it doesnt rinse it with distilled water.

Beautifully explained.

 

[Dylanamali]

yes.

 

[Dylanamali]

Beautifully explained.

thank you, troll =). rep me =P