Tricks of the trade

[cindyy]

wouldnt there be the same number of mols but just diluted so you need more volume ?

[naved_s9994]

Ohh, I thought she meant washed burette with water..hence diluted?
Hence, still <concentration  as c=n/v

[Stroodle]

uhhhhhhhhhhhh i don't like rules. I like intuition.


So if i have something in burette. And i wash it with water.

This means that there is less mol in the burette. Which means less mol wil react in the conical flask. Which means concentration in the flask is lower yes?

I the standard is in the burette you'll get a higher concentration, as you'll have a higher titre. If unknown is in the burette, it'll be a lower titre, so lower concentration.

[Martoman]

I mean.

You have HCL in the burette. But u rinse with water. So you now have less Hcl.

So less than expected NaOH in the conical flask will react.

[stonecold]

I just always bring it back to the titre being larger or smaller, cause that's what u directly use in your calculations to work out the amount of your unknown.

Just follow Stroodles rule... that is what i do, and it always works.

These rules are bull shit.

[Martoman]

Yeah this is so basic (excuse the pun), im still hazy though.

for eg (again)

Burette is rinsed. The unknown is in the conical flask. my gut says it goes higher. I don't know why. Wouldn't having less in burrette = less mol = lower concentration?

[Stroodle]

I just always bring it back to the titre being larger or smaller, cause that's what u directly use in your calculations to work out the amount of your unknown.

Just follow Stroodles rule... that is what i do, and it always works.

These rules are bull shit.

Yeah, our teacher taught us this and I've never got one of these questions wrong. It makes sense cause the titre is what you will use in your calculations to find the number of mole of the unknown.

[cindyy]

yes yes it does weew

[naved_s9994]

I just always bring it back to the titre being larger or smaller, cause that's what u directly use in your calculations to work out the amount of your unknown.

Just follow Stroodles rule... that is what i do, and it always works.

These rules are bull shit.

True...I mean for the last hour or so, Ive been trying to create all these formulas...for jackshit.. overcomplicated...I got totally confused with Stonecolds ones aswell (Sorry mate )....But Yea, Ive been doing it stroodles way in past, and its worked aswell. I shall stick with it!

[Stroodle]

Yeah this is so basic (excuse the pun), im still hazy though.

for eg (again)

Burette is rinsed. The unknown is in the conical flask. my gut says it goes higher. I don't know why. Wouldn't having less in burrette = less mol = lower concentration?

In this case the standard will be more dilute so you will need more of it to complete the reaction. So, since you have a higher titre - and this is where you get your number of mole of the unknown from - you'l have a higher concentration.

[cindyy]

I just always bring it back to the titre being larger or smaller, cause that's what u directly use in your calculations to work out the amount of your unknown.

Just follow Stroodles rule... that is what i do, and it always works.

These rules are bull shit.

True...I mean for the last hour or so, Ive been trying to create all these formulas...for jackshit.. overcomplicated...I got totally confused with Stonecolds ones aswell (Sorry mate )....But Yea, Ive been doing it stroodles way in past, and its worked aswell. I shall stick with it!

ive been guessing inthe past, but now i guess ill follow stroodles way tooo xD

[naved_s9994]

Yeah this is so basic (excuse the pun), im still hazy though.

for eg (again)

Burette is rinsed. The unknown is in the conical flask. my gut says it goes higher. I don't know why. Wouldn't having less in burrette = less mol = lower concentration?

Overestimated. Burette solution is diluted with water, so more is used.


(Beaten, by Stroodle )

[stonecold]

Yeah this is so basic (excuse the pun), im still hazy though.

for eg (again)

Burette is rinsed. The unknown is in the conical flask. my gut says it goes higher. I don't know why. Wouldn't having less in burrette = less mol = lower concentration?

In this case the standard will be more dilute so you will need more of it to complete the reaction. So, since you have a higher titre - and this is where you get your number of mole of the unknown from - you'l have a higher concentration.

My logic exactly.  This is how I explained it the first time haha, but no one liked it.  Everyone wanted a rule lol...

[Martoman]

Yeah this is so basic (excuse the pun), im still hazy though.

for eg (again)

Burette is rinsed. The unknown is in the conical flask. my gut says it goes higher. I don't know why. Wouldn't having less in burrette = less mol = lower concentration?

In this case the standard will be more dilute so you will need more of it to complete the reaction. So, since you have a higher titre - and this is where you get your number of mole of the unknown from - you'l have a higher concentration.

I get this, but even then. If your mol is less in the burette i cannot see why the mol in the other would increase.

[Stroodle]

Yeah this is so basic (excuse the pun), im still hazy though.

for eg (again)

Burette is rinsed. The unknown is in the conical flask. my gut says it goes higher. I don't know why. Wouldn't having less in burrette = less mol = lower concentration?

In this case the standard will be more dilute so you will need more of it to complete the reaction. So, since you have a higher titre - and this is where you get your number of mole of the unknown from - you'l have a higher concentration.

I get this, but even then. If your mol is less in the burette i cannot see why the mol in the other would increase.

The mole in the other doesn't increase. But when you do your calculations you get the amount of the unknown from working out the number of mole in the titre. So you'll end up with a higher concentration.