Question

While studying the decompoistion of gaseous `N_(2)O_(5)`, it is observed that a plot of logarithm of its partial pressure versus time is linear. What kinetic parameters can be obtained form this observation?
A. (i), (ii), (iii), (iv)
B. (iv), (iii), (ii)
C. (ii), (iii)
D. (i), (ii), (iii)

Answer 1

Correct Answer - C
This is the characteristic of a first oeder reaction as shown below
`k=(2.303)/(t)log(P_(0))/(p_(t))`
log `(P_(0))/(P_(t))=(k)/(2.303)t`
log `P_(0)-logp_(t)-(k)/(2.303)t`
or `{:(logp_(t)=,logp_(0),-,(k)/(2.303),t),(overset(uarr)(y),overset(uarr)(b),overset(uarr)(m),overset(uarr)(x)):}`
This equation is of the form `y=mx+b` . Thus, if we graph log `p_(t)1 versus time, we obtain a straigh line having a negative slope equal to `-k//2.303` and an intercept on `y-`axis equal to log `p_(0)` Thus, form the value of the slope, we can determine the rate constant:
`k=(-(slope))/(2.303)`