The pure form of sodium hydroxide is solid. Compared to the pure form, the aqueous form of the liquid is actually many times more volatile. For this very reason, it is advised that the bottles used to keep samples of NaOH be kept closed.
<u>Answer:</u> The value of
for the reaction is 1051.93 J/K
<u>Explanation:</u>
Entropy change is defined as the difference in entropy of all the product and the reactants each multiplied with their respective number of moles.
The equation used to calculate entropy change is of a reaction is:
![\Delta S^o_{rxn}=\sum [n\times \Delta S^o_{(product)}]-\sum [n\times \Delta S^o_{(reactant)}]](https://tex.z-dn.net/?f=%5CDelta%20S%5Eo_%7Brxn%7D%3D%5Csum%20%5Bn%5Ctimes%20%5CDelta%20S%5Eo_%7B%28product%29%7D%5D-%5Csum%20%5Bn%5Ctimes%20%5CDelta%20S%5Eo_%7B%28reactant%29%7D%5D)
For the given chemical reaction:

The equation for the entropy change of the above reaction is:
![\Delta S^o_{rxn}=[(2\times \Delta S^o_{(Cr_2O_3(s))})]-[(4\times \Delta S^o_{(Cr(s))})+(3\times \Delta S^o_{(O_2(g))})]](https://tex.z-dn.net/?f=%5CDelta%20S%5Eo_%7Brxn%7D%3D%5B%282%5Ctimes%20%5CDelta%20S%5Eo_%7B%28Cr_2O_3%28s%29%29%7D%29%5D-%5B%284%5Ctimes%20%5CDelta%20S%5Eo_%7B%28Cr%28s%29%29%7D%29%2B%283%5Ctimes%20%5CDelta%20S%5Eo_%7B%28O_2%28g%29%29%7D%29%5D)
We are given:

Putting values in above equation, we get:
![\Delta S^o_{rxn}=[(2\times (881.2))]-[(4\times (23.77))+(3\times (205.13))]\\\\\Delta S^o_{rxn}=1051.93J/K](https://tex.z-dn.net/?f=%5CDelta%20S%5Eo_%7Brxn%7D%3D%5B%282%5Ctimes%20%28881.2%29%29%5D-%5B%284%5Ctimes%20%2823.77%29%29%2B%283%5Ctimes%20%28205.13%29%29%5D%5C%5C%5C%5C%5CDelta%20S%5Eo_%7Brxn%7D%3D1051.93J%2FK)
Hence, the value of
for the reaction is 1051.93 J/K
The balanced chemical reaction is:
Na2SO4 + Ba(OH)2 = 2NaOH +BaSO4
We are given the amount of the reactants to be used. These values will be the starting point of our calculations.
0.0820 mol/L Ba(OH)2 (2.27 L solution) = 0.18614 mol Ba(OH)2
0.0664 mol/L Na2SO4 (3.06 L solution) = 0.20318 mol Na2SO4
The limiting reactant is the Ba(OH)2. The amount for this compound will be used.
0.18614 mol Ba(OH)2 (1 mol BaSO4 / 1 mol Ba(OH)2 ) (233.43 g BaSO4 / 1 mol BaSO4)= 43.4507 g BaSO4