Consider the strong electrolytes ZmXn, UmYp and VmXn. Limiting molar conductivity ( Λo ) of UmYp and VmXn are 250 and 440Scm2mol−1, respectively. The value of ( m+n+p ) is ____. Given:
Ion
Zn+
Up+
Vn+
Xm−
Ym−
λ0(Scm2mol−1)
50.0
25.0
100.0
80.0
100.0
λ0 is the limiting molar conductivity of ions The plot of molar conductivity ( Λ ) of ZmXn vs c1/2 is given below.
Answer: 7
Solution
From the given limiting molar conductivities:
For UmYp: 25m+100p=250⇒m+4p=10 ... (1)
For VmXn: 100m+80n=440⇒5m+4n=22 ... (2)
From the graph extrapolation, Λ∘(ZmXn)=340: 50m+80n=340⇒5m+8n=34 ... (3)
Subtracting (2) from (3): 4n=12⇒n=3
Substituting in (2): 5m+12=22⇒m=2
Substituting in (1): 2+4p=10⇒p=2
Therefore, m+n+p=2+3+2=7.
JEE Advanced · 2022 · 28 Aug 2022 · Paper 2 · Integer answer