Thermodynamics T4

the surfactant N-dodecyl-N,N-dimethylpropanesultaine is

• anionic

• cationic

• non ionic

• zwitteronic

the molar Gibbs energy of micelle formation  $\Delta G^{mic}$  is equal to 

• RTln(CMC)

• RTexp(CMC)

•  $\mu_{surfact}^0$  

•  $\mu_{surfact}^0\left(solvent\right)$  

what is the value of the packing parameter for a cylindrical micelle?

• 0.5

• 1

• 0.33

• 0

which is the plot of a Langmuir isotherm?

• A

• B

• C

• D

which of the following statements about the Marangoni effect is false?

• is due to gradient of surface tension

• can be driven by temperature gradient

• can be driven by concentration gradient

• can only occur if a surfactant is present

which of the following statements is true for ionic surfactants?

• Above the Krafft point the solubility is quite low

• above the Krafft point the solution does not contain micelles

• Below the Krafft point surfactants are usually more effective

• At the Krafft point surfactant solubility equals CMC

what is the phase rule for gas/adsorbate equilibrium? (N = number of component, p = number of phases)

• F = N - p + 2

• F = N - p + 3

• F = N - p + 1

• F = N - p

when all sites of a solid surface become occupied, the adsorbed molecules are said to form a

• monolayer

• multilayer

• bilayer

• liquid

the Plateau-Rayleigh instability

• is driven by surface maximization

• explains why a falling stream of water breaks up into droplets

• occurs by a change of volume

• does not depend on surface tension