Stoichiometry - FIITJEE REE 19

1.16 g CH3(CH2)nCOOH was burnt in excess air & the resultant gases ( CO2 & H2O )were passed thru excess NaOH solution .

The resulting solution is divided into 2 equal parts.One part required 50 mL of 1 N Hcl for neutralization using phenolphthalein as indicator. Another part required 80 mL of 1 N Hcl for neutralization using methyl orange as indicator.

Find the value of n?

10 Answers

4
UTTARA ·

Any tries??

1
Bicchuram Aveek ·

Anyone for this ?? I'm trying ..

1
abcd ·

n=3

1
abcd ·

what does fitjeeree 19 stand for?

1
Bicchuram Aveek ·

Ishan plzzz show ur working

1357
Manish Shankar ·

is it 4?

4
UTTARA ·

I don't know the ans

1357
Manish Shankar ·

CH3(CH2)nCOOH→(n+2)CO2
mill moles of CH3(CH2)nCOOH=1.16*1000/(12*(n+2)+2n+4+32)=1.16*1000/(14*(n+2)+32)

millimoles of CO2=1.16*1000/(14+32/(n+2))

CO2+NaOH=Na2CO3

millimoles of CO2=milllimoles of Na2CO3=x
millimoles of NaOH left=y

x/2+y=50
x+y=80

so x=60

30=1.16*1000/(14+32/(n+2))

14+32/(n+2)=1160/60=58/3
32/(n+2)=58/3-14=16/3
n+2=6

n=4

4
UTTARA ·

Thanks Manish Sir

1
Unicorn--- Extinct!! ·

The answer given is 4 :)

Your Answer

Close [X]