Answer : The correct option is, (b) +115 J/mol.K
Explanation :
Formula used :
where,
= change in entropy
= change in enthalpy of vaporization = 40.5 kJ/mol
= boiling point temperature = 352 K
Now put all the given values in the above formula, we get:
Therefore, the standard entropy of vaporization of ethanol at its boiling point is +115 J/mol.K
Explanation:
Let the age to be found in years is y.
Hence,
= (\frac{1}{2})^{\frac{y}{5730yr}}
Solve for y as follows.
0.53913 = (\frac{1}{2})^{\frac{y}{5730yr}}
Now, taking log on both the sides as follows
log 0.53913 =
=
z =
= 5107 years
Thus, we can conclude that the time since death is 5107 years.