Physical Pharmacy
???????? Surface and Interfacial tension????????
1). HLB value of detergent is
A) 9 to 12
B) 13 to 16
C) 6 to 9
D) 14 to 16
2). Chemically SPANS are called as
A) sorbiton ester of fatty acids
B) polyoxyethylene sorbiton esters
C) fatty acid of P.E.G esters
D) alcohol PEG esters
3). Rapid increase in solubility of a surfactant solution alcohol above a definite temperature is
A) cloud point
B) Kraft point
C) CMS
D) triple point
4). Surface tension of liquid is at critical temperature
A) zero
B) one
C) Negative
D) maximum
5). The cleaning action of soaps and detergents is due to
A) Internal friction
B) high hydrogen bonding
C) surface tension
D) viscosity
6). A water exposed to atmosphere is an example of
A) Solid surface
B) Liquid surface
C) Gas interface
D) Liquid interface
7). Interfacial tension are invariably _______ surface tension.
A) Less than
B) Equal to
C) More than
D) Double than
8). Surface tension is usually defined as the change in surface free energy per unit change in
A) Length
B) Area
C) volume
D) Density
9). The formula used for the determination of surface tension by capillary rise method
A) 2y= πrcosΦ
B) 2y=πr2CosΦ
C) 2y=hrdg
D) 2y=hr2pg
10). With rise in temperature surface tension of a liquid
A) Increases
B) Decreases
C) remains the same
D) None of the above
Answers
1. B (13-16)
2. A (Sorbiton ester of fatty acid)
3. B (kraft point)
4. A (zero)
5. C(surface tension )
6. B (Liquid surface )
7. A(Less than )
8. B(Area)
9. C(2y=hrdg)
10. B (Decreases )
Â
