this was the easiest question of the question paper.
u will see that only the 2nd option had 6 molecules of NH3.so rest have to be wrong.
hope i had checked that earlier[2][2][2][2][2]
but just to verify the correctness of the answer,dont u think my method is correct..and i dont think 3.3 can be approximated as 3 can it?
Q. A solution containing 2.675g of CoCl3. 6NH3 (molar mass = 267.5 g/mol) is passed through a cation exchanger. The chloride ions obtained in solution were treated with excess of AgNO3 to give 4.78g of AgCl(molar mass = 143.5 g/mol). The formula of the complex is? (At mass of Ag = 108u)
I didn't understand the FIITJEE solution, so if someone could please explain the approach to this question, I would be grateful.
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i dint get the ans too...this is how i proceeded..
the number of ionisable Cl- ions per molecule of the complex is important as they are rthose ions which form the ppt with AgNO3.
Cl- + AgNO3 → AgCl + NO3-
35.5 143.5
143.5 g of AgCl is given by 35.5 g of Cl- ions
4.78 g of AgCl is given by 1.18 g of Cl- ions
let the no of ionisable Cl- ions per mole of complex be x.
no of moles of complex=0.01
wt of Cl- in 1 mole=35.5x
wt of Cl- in 0.01 moles=0.355x
0.355x=1.18
x=3.3 not getting the answer[2]
what was the answer given pritish?
someone plz tell me my mistake,or provide the solution for this sum..
We've simply got to equate the wt. of chlorine we get frm both.
n x 2.675267.5 x 35.5 = 35.5143.5 x (4.78)
(where n = moles of Cl- ions we get frm ionisation of 1mole complx.)
which gives "n" ≈3
Oh sry...was in such a hurry ki didnt see Arka had already posted the solution :O
Thts right arka, it is exactly wht i've done. [1]