National Titration Comp (1 Viewer)

[d00d]

whos doing it? are there any tips? the method is way harder this time, the filtering takes aggggges...

 

[hipsta_jess]

i havent even heard of it...but i have to say it is the saddest thing i have heard tonight.

 

[spice girl]

a tip? don't bother filtering. just wait till all the fairy dust settles, and pipette the liquid out.

we had no problems last time...

 

[iambored]

Originally posted by d00d
whos doing it? are there any tips? the method is way harder this time, the filtering takes aggggges...

y is it harder? u gotta filter?? it's not the same???

 

[d00d]

spicegirl: how can u not filter? u need to filter out the Ba2SO4 so all u've got left is the acid, and then u make it up to the 100mL mark.

iambored: its a lot longer and harder this time, 3 hrs of it. u gotta make up the primary standard urself and in the second titration they deliberately contaminated it with Ba2SO4 which is why u have to filter it.

to get gold u need a result within 1% of the correct answer, i wonder how many ppl got it last year?

 

[spice girl]

Originally posted by d00d
spicegirl: how can u not filter? u need to filter out the Ba2SO4 so all u've got left is the acid, and then u make it up to the 100mL mark.

iambored: its a lot longer and harder this time, 3 hrs of it. u gotta make up the primary standard urself and in the second titration they deliberately contaminated it with Ba2SO4 which is why u have to filter it.

to get gold u need a result within 1% of the correct answer, i wonder how many ppl got it last year?

to filter or not to filter...

you have to consider which would cause you more error: the volume displacement caused by the BaSO4 (which to my recollection is waaay less than 1ml). Considering that the volumetric is at least 100mL (i can't remember if 100 or 250), that's less than 1% error. Remember that adding a drop too many (to make up the mark) may give you more volume error than the BaSO4 volume.

On the contrary, if you filter, you have to wash the damn filter (cos the KHP will get soaked in the paper). This means you have to use less water to dissolve ALL the KHP (which is hard to tell when all the KHP is dissolved, since both KHP and BaSO4 is white). In addition, filtering may mean splashing if you're not careful. Also, you have to be careful when you wash the filter that you don't accidentally add more water than you need.

IMHO, filtering is being fussy. We had no problems getting more golds than non-golds. Also i managed to finish in 90min

 

[BlackJack]

lol, that's excellent. just excellent.

 

[skool_angel]

when is this titration comp?
whos running it?

 

[iambored]

Originally posted by d00d
spicegirl: how can u not filter? u need to filter out the Ba2SO4 so all u've got left is the acid, and then u make it up to the 100mL mark.

iambored: its a lot longer and harder this time, 3 hrs of it. u gotta make up the primary standard urself and in the second titration they deliberately contaminated it with Ba2SO4 which is why u have to filter it.

to get gold u need a result within 1% of the correct answer, i wonder how many ppl got it last year?

oh wow
glad we didn't get in then!

 

[Misturi]

Was it Held at Bondi?? I went to one and l got the second lowest out of about 5 schools.

 

[dark turtle]

Originally posted by sarah_#1_eel
Was it Held at Bondi?? I went to one and l got the second lowest out of about 5 schools.

I think there was more than 5.

 

[Darkiris]

Originally posted by d00d
whos doing it? are there any tips? the method is way harder this time, the filtering takes aggggges...

Originally posted by d00d

to get gold u need a result within 1% of the correct answer, i wonder how many ppl got it last year?

Originally posted by snow bum
Surely trying to filter out BaSO4 would be like banging your head against a brick wall?

a) i did the national titration competition last year

b) we totally fucked up this year in the state competition, so much so that we didn't place well enough to get into nationals this year -_-

c) i did recieve a gold medal last year at the nationals

d) the method looks hard but it really isn't

e) if you don't filter it masks the end point, though some schools dont' bother filtering to apparetnly "save time" and are probably use to doing it with that method

f) no the filtering is fine, all the impurities get put out and all the dissolved solids filter through nicely

g) you don't need to be a rocket scientist to get a gold medal you just have to be lucky and good at estimating if you make a mistake, i spilt my solution while making it

h) there is enough time to use the filtering process, all you need to be is patient and also flush all the dissolved solids through the filter paper with distilled water, therefore when you're making up your solution try and use as little water as possible so you can rinse the filter paper a greater number of times to be sure everything goes through

i) be patient through the whole process (ie every step), and do something else while it's filtering.

j) everyone has a chance at getting a gold medal, you just need a low error margin

k) quite a few people recieved a gold medal at the UNSW division last year of the nation titration competition

 

[Darkiris]

Originally posted by spice girl
to filter or not to filter...

you have to consider which would cause you more error: the volume displacement caused by the BaSO4 (which to my recollection is waaay less than 1ml). Considering that the volumetric is at least 100mL (i can't remember if 100 or 250), that's less than 1% error. Remember that adding a drop too many (to make up the mark) may give you more volume error than the BaSO4 volume.

On the contrary, if you filter, you have to wash the damn filter (cos the KHP will get soaked in the paper). This means you have to use less water to dissolve ALL the KHP (which is hard to tell when all the KHP is dissolved, since both KHP and BaSO4 is white). In addition, filtering may mean splashing if you're not careful. Also, you have to be careful when you wash the filter that you don't accidentally add more water than you need.

IMHO, filtering is being fussy. We had no problems getting more golds than non-golds. Also i managed to finish in 90min

spice girl is right

it's really all up to preference

personally i did splash just before the filtering step therefore losing some of my solution, after a lot of "oh my god"s i did filter and i got a gold

 

[dark turtle]

nope, this isn't our one sarah. this is a NATIONAL comp. I can't believe I was stupid enough to believe you. oh well, not that much time was wasted.

 

[jm1234567890]

lol, i didn't even make it past the region... too boring, i'm too impatient

 

[jayz]

For no reason what so ever.

OUR SCHOOL CAME 9th!!

 

[Darkiris]

Originally posted by jm1234567890
lol, i didn't even make it past the region... too boring, i'm too impatient

i like

i'm impatient but it's fun

 

[pri]

there is a strange satisfaction with achieving a good titration score, as nerdalicious as this sounds I enjoyed the regionals

a person from my school did a perfect titration in the nationals (thats a score of 0 for those who dont know)

in the regionals one of our teams had 0, 0 and 50 for their scores..

the person who got 50 was a tad upset I think...

 

[McLake]

Upset with 50?? That's like an error of 7mL ...

 

[pri]

well considering the other team mates got 0, 0 , they could have gotten into the nationals if the score was less than 50