<u>Answer:</u> The experimental van't Hoff factor is 1.21
<u>Explanation:</u>
The expression for the depression in freezing point is given as:

where,
i = van't Hoff factor = ?
= depression in freezing point = 0.225°C
= Cryoscopic constant = 1.86°C/m
m = molality of the solution = 0.100 m
Putting values in above equation, we get:

Hence, the experimental van't Hoff factor is 1.21
Answer:
8.354 nanometers
Explanation:
To treat a diffusive process in function of time and distance we need to solve 2nd Ficks Law. This a partial differential equation, with certain condition the solution looks like this:

Where Cs is the concentration in the surface of the solid
Cx is the concentration at certain deep X
Co is the initial concentration of solute in the solid
and erf is the error function
Then we solve right side,

And we need to look up the inverse error function of 0.001964 resulting in: 0.00174055
Then we solve for x:

Answer:
both drugs will be equally effective
Explanation:
A racemic mixture is a substance that contains a 50/50 mixture of the (+) and (-) enantiomers of an optically active compound.
It is important to note that even if a drug occurs as a racemic mixture, only the biologically active enantiomer will interact with the substrate on which the drug acts. The other enantiomer present is just irrelevant. Similarly, its presence does not affect the biological activity of the active enantiomer.
Hence, both Prilosec and Nexium are both equally effective.