A) 18.5
B) 15
C) zero
D) None of these
Correct Answer: A
Solution :
Entropy of a system is a measure of its molecular disorder. The greater the disorder, greater is the entropy. The charge in entropy is given by \[dS=\frac{dQ}{T}\] \[=\frac{Heat\text{ }absorbed}{Absolute\text{ }temperature}\] Also,\[dQ=mL\]where, m is mass and L the latent heat. Given, \[m=15\text{ }g,\text{ }L=80\text{ }cal/g\] \[\therefore \] \[dQ=15\times 80=1200cal\] \[dQ=1200\times 4.2=5040J\] Hence, change in entropy is \[dS=\frac{5040}{273}=18.46\] \[\approx 18.5\]
You need to login to perform this action.
You will be redirected in
3 sec
