Chemo P5 tips

[xxfarhaxx]

would u please quote the question and the paper in which it is

i rely cnt remmbr whch ppr it is in..i even tried goin tru da pprs bt cudnt find da qustion!

 

[ijjukittu]

the difference between a normal test tube and graduated test tube is that graduated means having measurement lines on them...so basically if you have to draw it or state it....draw lines on the test tube side....or if your writing then just state graduated test tube....hope that helps!

thank u

 

[Alevel Romeo]

can anyone please upload solved paper of may june 2012 chemistry paper 52?? really confused on it! and cant get it even after seeing mark scheme!!
thankx in advance

 

[Alevel Romeo]

can anyone please upload solved paper of may june 2012 chemistry paper 52?? really confused on it! and cant get it even after seeing mark scheme!!
thankx in advance

 

[Alevel Romeo]

can anyone please upload solved paper of may june 2012 chemistry paper 52?? really confused on it! and cant get it even after seeing mark scheme!!
thankx in advance

 

[Mr.Smart]

hey can anyone tell me in may.june 09 question no.2 we have to find the solubilities...but my solubilitites are coming more thann 100? is that okay?

no they can't be more than 100
mine are less than 75
check ur calculation

 

[Mr.Smart]

thanks a million 4 sharing ur practical xperience.

can u please write da procedure of oct 2010 52???

the easiest ppr eever

 

[xxfarhaxx]

no they can't be more than 100
mine are less than 75
check ur calculation

wel my solubility was more than 100 n my teacher told it ws ok..even the examine report says that ryt?

 

[ijjukittu]

When preparing a solution of a fixed concentration from a given parent solution of concentration , say, 2.0 mol/dm3

A. We are required to prepare a solution of concentration of 1.0 mol/dm3 with volume 250 cm3 ( the concn cannot be greater than 2 !!!!!!!!!!!!!!)
a. Add 100 cm3 of the parent solution to a volumetric flask of marking at 250 cm3
b. Top off with water to the mark of 250 cm3. Use a wash bottle for this purpose to have greater control over the addition process

When required to prepare 250 cm3 of 0.5 mol/dm3 solution of a crystal of Mr 50g

First realize that we need only 250 cm3, not 1 dm3
Now in 250 cm3 there will be: 50/4 = 12.5 g of the solid

So, first add 12.5 g of solid to 50 cm3 of water in a BEAKER ( not the volumetric flask yet). Also note that the volume of water is less than 250 cm3.
Stir properly and if the solid doesn't dissolve add more water until it fully dissolves
Then transfer the solution from the beaker to a volumetric flask. Remember to rinse the beaker with water and transfer the solution to the volumetric flask
Stopper the flask and shake properly
Finally, add the required volume of water to make the solution upto 250 cm3 USE A FUNNEL OR YOU RISK OVERSHOOTING THE MARK

can anyone please tell me why we have done 50/4?

 

[faangelica]

i

the file asks for credentials ..

i cant find these notes ,

 

[Mr.Smart]

wel my solubility was more than 100 n my teacher told it ws ok..even the examine report says that ryt?

but how is that coming greater than 100? using normal calculations, mine is less than 70 :/

 

[anishniroula]

thank you pranav dai. You still rock in our college..(kings college)

 

[ijjukittu]

InO/N 2010(53) question..no.1 (d) can anyone tell me the volume of H2O2 + vol. of water & conc. of H2O2????

 

[xxfarhaxx]

but how is that coming greater than 100? using normal calculations, mine is less than 70 :/

this is how i calculated it.. (mass of solid/ mass of water)*100
i guess u wud hav used the mass of solution instead of water..when we did this mistake my teacher told that mass of the solution is not same as the mass of water!

 

[ijjukittu]

this is how i calculated it.. (mass of solid/ mass of water)*100
i guess u wud hav used the mass of solution instead of water..when we did this mistake my teacher told that mass of the solution is not same as the mass of water!

Nop!!!!! mass of solid/ mass of water x 100 ...!

 

[xxfarhaxx]

Nop!!!!! mass of solid/ mass of water x 100 ...!

rely! then you shud b gettin more than 100..wel this is my calculation for the frst temp 20
(77.9/43.5)*100 = 179.1

 

[zain786]

thank u

no problem!

 

[donorsolutions]

here are some chem p5 notes

 

[N.M]

When preparing a solution of a fixed concentration from a given parent solution of concentration , say, 2.0 mol/dm3

A. We are required to prepare a solution of concentration of 1.0 mol/dm3 with volume 250 cm3 ( the concn cannot be greater than 2 !!!!!!!!!!!!!!)
a. Add 100 cm3 of the parent solution to a volumetric flask of marking at 250 cm3
b. Top off with water to the mark of 250 cm3. Use a wash bottle for this purpose to have greater control over the addition process

When required to prepare 250 cm3 of 0.5 mol/dm3 solution of a crystal of Mr 50g

First realize that we need only 250 cm3, not 1 dm3
Now in 250 cm3 there will be: 50/4 = 12.5 g of the solid

So, first add 12.5 g of solid to 50 cm3 of water in a BEAKER ( not the volumetric flask yet). Also note that the volume of water is less than 250 cm3.
Stir properly and if the solid doesn't dissolve add more water until it fully dissolves
Then transfer the solution from the beaker to a volumetric flask. Remember to rinse the beaker with water and transfer the solution to the volumetric flask
Stopper the flask and shake properly
Finally, add the required volume of water to make the solution upto 250 cm3 USE A FUNNEL OR YOU RISK OVERSHOOTING THE MARK

Aoa wr wb, can somebody plz explain...

 

[blessed one]

walikum-us-salam wr wb
main agai