0.5 mol of salt (NaCl) is dissolved in 4.5 mol of water. What is the increase in entropy?

Answer

a. 13.5 J/K

b. 84 J/K.

c. 9.8 J/K.

d. 2500 J/K.

Answer is 13.5 J/K. Use the formula (Delta S) = -(n)R(aLNa + bLNb) Where a and b are mole fractions Delta S = -(5.0 mol)(8.314)(.1LN(.1) + .9LN(.9))