StepWorking
01Given
Graph of log(x/m) vs logp is a straight line inclined at an angle of 45∘ with intercept equal to 0.6020. Pressure p=0.4 atm. Given log2=0.3010.
02Find
The mass of gas adsorbed per unit mass of adsorbent, mx, expressed in the form N×10−1 to find integer N.
03Strategise
Freundlich adsorption isotherm is given by mx=kp1/n. In logarithmic form:
log(mx)=logk+n1logp
Here, slope mline=n1=tan45∘=1 and intercept c=logk=0.6020.
Find k using log2=0.3010, then compute mx=kp1/n.
04Execute
Slope =n1=tan45∘=1.
logk=0.6020=2×0.3010=2log2=log(22)=log4⟹k=4.
Now calculate mx at p=0.4 atm:
mx=4×(0.4)1=1.6=16×10−1
Thus, the integer value is 16.
✓Verify
Check: log(1.6)=log(16/10)=4log2−1=4(0.3010)−1=1.2040−1=0.2040.
From the equation: log(x/m)=0.6020+1×log(0.4)=0.6020+(2(0.3010)−1)=0.6020−0.3980=0.2040. Matches perfectly.