Another question [1 mark] (1 Viewer)

[kooltrainer]

[1] Are there isomers for esters? if so, name an isomer for propyl propanoate [1mark]


[2] During your HSC course, u used gravimetric analysis to analyse sulfate content of lawn fertilisers. Student A used 2 grams of fertiliser, precipitated it and found the percentage composition of sulfate in soil.. Student B used 4 grams of fertiliser, precipitated and determined percentage composition.. Which student would give the most accurate result? [1mark]

 

[minijumbuk]

Yes.

Ethyl Butanoate.

 

[kooltrainer]

really?.. so do u jus move the ester linkage left and right to obtain the isomer? okay thx
what abt question 2?

 

[tommykins]

really?.. so do u jus move the ester linkage left and right to obtain the isomer? okay thx
what abt question 2?

B should as he used more of the sample allowing a more precise reading to be made.

(It's kinda like how a standard solution should relatively has a high molar mass, to allow exact measurements to be made easier)

 

[minijumbuk]

really?.. so do u jus move the ester linkage left and right to obtain the isomer? okay thx
what abt question 2?

Well the definition of an isomer is just any substance with the same number of atoms of specific elements, with a different structural formula.

 

[kooltrainer]

B should as he used more of the sample allowing a more precise reading to be made.

(It's kinda like how a standard solution should relatively has a high molar mass, to allow exact measurements to be made easier)

yeh i dun get that... how would more sample allow greater accuracy.. and i dunno how it relates to standard solution..they're separate things

 

[minijumbuk]

yeh i dun get that... how would more sample allow greater accuracy.. and i dunno how it relates to standard solution..they're separate things

I'm guessing it kinda goes like this:

You have to remember that fertilisers aren't uniform in concentration. There are areas where there is more mass of sulfate, and there are areas where there are less.

Imagine yourself making Chicken Caesar. If you take 1 spoon of it, there is a huge change that you will only pick up a piece of chicken and little or no lettuce. If you use your conclusion based on this, you'll conclude that there is less lettuce than the amount that is actually there. If you take around 10 spoons, however, then you'll incresae the likelihood of scooping up some lettuce as well as chicken. Then, you can give a more accurate calculation of how much lettuce there is in the salad.

Ok, now imagine that lettuce is sulfate, and chicken is all the other crap in the fertiliser.

 

[kooltrainer]

lol, like ur analogy.. i get it now

 

[vds700]

I'm guessing it kinda goes like this:

You have to remember that fertilisers aren't uniform in concentration. There are areas where there is more mass of sulfate, and there are areas where there are less.

Imagine yourself making Chicken Caesar. If you take 1 spoon of it, there is a huge change that you will only pick up a piece of chicken and little or no lettuce. If you use your conclusion based on this, you'll conclude that there is less lettuce than the amount that is actually there. If you take around 10 spoons, however, then you'll incresae the likelihood of scooping up some lettuce as well as chicken. Then, you can give a more accurate calculation of how much lettuce there is in the salad.

Ok, now imagine that lettuce is sulfate, and chicken is all the other crap in the fertiliser.

good analogy...makes me hungry though

 

[minijumbuk]

lol, many of my friends understand chemistry concepts when I use slightly humorous analogies xD

 

[tommykins]

I'm guessing it kinda goes like this:

You have to remember that fertilisers aren't uniform in concentration. There are areas where there is more mass of sulfate, and there are areas where there are less.

Imagine yourself making Chicken Caesar. If you take 1 spoon of it, there is a huge change that you will only pick up a piece of chicken and little or no lettuce. If you use your conclusion based on this, you'll conclude that there is less lettuce than the amount that is actually there. If you take around 10 spoons, however, then you'll incresae the likelihood of scooping up some lettuce as well as chicken. Then, you can give a more accurate calculation of how much lettuce there is in the salad.

Ok, now imagine that lettuce is sulfate, and chicken is all the other crap in the fertiliser.

Thanks for that, I really didn't know how else to put it.