Percentage composition of nitrogen in ammonium sulfate? (2 Viewers)

[seventhroot]

Dude stfu -.- so annoying, do you even chem?

inb4sole

Okay, then from the moles of Nitrogen you'd find the mass.
So Mass of Nitrogen = moles of Nitrogen x molar mass of nitrogen.

Then iirc you put:
(mass of nitrogen/14.21) x 100 = w/w%

I'm not sure, been ages since I did this. Someone pls confirm.

confirmed

 

[screwuhsc]

Btw that was to cheekym8

 

[seventhroot]

Btw that was to cheekym8

we got that part

outb4derails

 

[lpodtouch]

I'll just post the whole question.

You are given to analyse the concentration of nitrogen in a sample of ammonium sulfate fertilizer. Precipitate the sulfate ion from solution using barium nitrate and then use the mass of precipitate formed to determine concentration of nitrogen.

Mass of fertilizer: 14.21
Mass of barium sulfate precipitated: 1.15
Determine percentage of composition of nitrogen in fertilizer

1. First you have to write out a balanced chemical equation:
Ba(NO3)2 (aq) + (NH4)2SO4 (aq) -> BaSO4 (s) + 2NH4NO3 (aq)

2. Given that the mass of BaSO4 is 1.15g, you are able to calculate the moles utilising the equation that n = m/M
n = 1.15/molar mass of BaSO4 (don't have a Periodic Table with me)

3. Given that the objective is to find the % composition of nitrogen in ammonium sulfate, utilise molar ratios.
(NH4)2SO4 : BaSO4 = 1 : 1
Therefore the no. of moles for BaSO4 is equal to the no. of moles for (NH4)2SO4

4. Afterwards, find the molar mass of (NH4)2SO4, utilising the mole value calculated for the above (n = m/M).

5. In order to find the mass of nitrogen within the provided sample, find the % of nitrogen in the molar mass of ammonium sulfate (i.e. 2(14.01)/[2(14.01 + 4(1.008)) + 32.07 + 4(16)].

6. Multiply this value with the molar mass of ammonium sulfate that was calculated in the fourth step, to find the overall mass of nitrogen in the fertiliser sample.

7. Using the mass of nitrogen in the sixth step, divide it by the mass of the fertiliser (14.21g) and multiply by 100 to receive the w/w%.

I'm not sure whether this is all correct though. :/ Good luck.

 

[Cleverusername5321]

molecular mass 2N/molecular mass (NH4)2SO4 * 100