Powders

Question 1

What are the properties of mesopause molecules (4 properties)

Answer 1

1. Behave like organic molecules
2. elongated or rectilinear molecules
3. rigid molecules
4. strong dipoles and easily polarisable groups

Question 2

What are 4 uses of mesophase molecules

Answer 2

temperature sensor
display-liquid crystals provide colours
stabilisation of emulsions. by increasing viscosity
improve solubilisation drugs

Question 3

Advantages of solid dosage form

Answer 3

markedly better chemical stability
when dry, does not promote microbial growth
lower bulk volume
ease of handling, added convenience
flexible, single or multiple chemical components

Question 4

properties of crystalline structures

Answer 4

orderly arrangement 
anisotropic (sharp X-ray diffraction patterns) 
sharp melting points 
definite heat of fusion 
more stable, chemically

Question 5

properties of amorphous structures

Answer 5

no arrangement 
isotropic 
melt over a range 
no definite heat of fusion 
more liable to degradation

Question 6

What are the 3 most used preparation methods of amorphous forms

Answer 6

milling
spray drying
freeze drying

Question 7

How do you determine the crystallinity/polymorphism of a particle

Answer 7

X-ray diffraction 
melt behaviour (visual-hot stage microscopy, differential scanning calorimetry) 
raman spectroscopy 
infrared spectroscopy 
nuclear magnetic resonance spectroscopy

Question 8

visible light wavelength

Answer 8

400-800 nm

Question 9

X-ray wavelength for crystallography powder diffraction

Answer 9

0.1 nm

Question 10

advantages of Raman spectroscopy

Answer 10

provide distinct spectroscopic property of a material
fast measurement time
able to measure from small spot size to a few microns

Question 11

uses of Raman spectroscopy

Answer 11

non-desctructive, microscopic, chemical analysis application