States of Matter and properties of matter:
State of matter, changes in the state of matter, latent heats, vapour pressure, sublimation critical point, eutectic mixtures, gases, aerosols– inhalers, relative humidity, liquid complexes, liquid crystals, glassy states, solid-crystalline, amorphous & polymorphism.
Physicochemical properties of drug molecules:
Refractive index, optical rotation, dielectric constant, dipole moment, dissociation constant, determinations and applications
States and Properties of Matter and
Physicochemical Properties of Drug Molecules States of Matter and Properties of Matter States of Matter Changes in the State of Matter Latent Heat Vapour Pressure Sublimation Critical Point Eutectic Mixtures Gases Aerosols Inhalers Relative Humidity Liquid Complexes Liquid Crystals Glassy State Solids Physicochemical Properties of Drug Molecules: Determinations and Applications Refractive Index Optical Rotation Dielectric Constant Dipole Moment Dissociation Constant
Physical science, includes chemistry and physics, and is usually thought of as the study of the nature and properties of matter and energy in non-living systems. Matter is the “stuff” of the
universe — the atoms, molecules and ions that make-up all physical substances. Matter is anything that has mass and takes up space. There are five known phases, or states, of matter:
solids, liquids, gases, and plasma and Bose-Einstein condensates. The main difference in the structures of each state is in the densities of the particles. Adding energy to matter causes a physical change causing matter to move from one state to another. For example, adding thermal energy (heat) to liquid water causes it to become steam or vapour (a gas). Taking away energy also causes physical change, such as when liquid water becomes ice (a solid) when heat is
removed. These changes in states of matter and their inherent properties are studied and are applied in various area of pharmacy. Thus the objective of studying this chapter is to :
• Understand characteristics of states of matter.
• Understand the different physical properties of each state of matter.
• Study applications of states of matter in synthesis of drugs, analysis and design and development of dosage forms.
• Apply physical properties in various field of pharmacy such as raw material testing, preformulation, formulation characterization and stability studies etc.
1. What are homogeneous and homogeneous mixtures? Give four pharmaceutical examples
2. How is a chemical change different from a physical change?
3. What is the difference between a homogeneous and a heterogeneous mixture?
4. Explain how transition takes place between states of matter.
5. What do you understand from the terms sublimation and condensation?
6. What is vapour pressure of liquid? Enlist and explain methods to determine it.
7. How boiling point of liquid is determined if molar heat of vapourization is known?
8. Describe the terms critical temperature and critical pressure with reference to water.
9. With the help of graph explain energy distribution in the molecules of liquid at two different temperatures.
10. Write the difference between a gas and a vapour.
11. Write note on characteristics of gaseous state.
12. What is ideal gas and real gas?
13. What is gas law? Write statements of Boyles’s law, Charles law and Avogadro’s law.
14. Derive an equation of ideal gas law.
15. Express gas constant in three different energy units.
16. Explain the significance to the development of the kinetic molecular model of the observation that the ideal gas law works well only at low pressure.
17. Give a brief molecular explanation for the observation that the pressure of a gas at fixed temperature increases proportionally with the density of the gas.
18. Give a brief molecular explanation for the observation that the pressure of a gas confined
to a fixed volume increases proportionally with the temperature of the gas.
19. Give a brief molecular explanation for the observation that the volume of a balloon
increases roughly proportionally with the temperature of the gas inside the balloon.
20. Explain why there is a correlation between high boiling point and strong deviation from
the ideal gas law.
21. Which parameters of real gases differ from ideal gases?
22. Obtain relationship between van der Waals constants and critical constants in a van der
23. Discuss applications of ideal gas law.
24. Calculate the number of moles of a gas present in a container of 0.0432 m3
temperature and pressure 21 °C and 15.4 atm.
25. A 40 L cylinder contains 30.5 g of nitrogen gas at 21 °C. What is the pressure inside the
cylinder expressed in psi units?
26. Calculate the volume occupied by 60 g of oxygen gas at a temperature and pressure of
25 °C and 24 atm, respectively.
27. What are aerosol and inhalers? Give some pharmaceutical examples of each of them.
28. What are liquid crystals? Classify them and write about its pharmaceutical applications.
29. Define the terms:
(a) Matter (b) Substance
(c) Element (d) Latent heat of vapourization
(e) Latent heat of fusion (f) Boiling point
(g) Melting point (h) Freezing point
(i) Isotropy (j) Crystal lattice
(k) Anisotropy (l) Crystalline solid
(m) Amorphous solid.
30. Explain theory of Bragg’s method of crystal analysis.
31. What are point groups and space groups in crystal units?
32. Write note on Bravis lattice.
33. What are minimum numbers of atoms per unit cell of sodium chloride?
34. Explain different elements of symmetry of cubic unit cell.
35. Give difference between:
(a) Primitive unit cell and non-primitive unit cell.
(b) Plane of symmetry and axes of symmetry.
36. Calculate co-ordination number in a cubic body centered and face centered crystals.
37. Derive the relationship; nλ = 2d sin θ.
38. Enlist and explain various imperfections observed in crystals.
39. Write characteristics of crystals.
40. What do you understand from the term glass transition temperature?
41. Write about physical properties of amorphous solids.
42. Differentiate between melting and glass transition temperatures.
43. Describe in detail characterization of amorphous solids.
44. Write note on significance of amorphous state in pharmaceuticals.
45. Differentiate between crystalline and amorphous solids.
46. What do you mean by polymorph? Classify them and describe methods to identify
47. Explain significance of polymorphism in pharmaceuticals with some examples.
48. What is transition temperature? Describe methods to determine it.
49. Differentiate between solvates and polymorphs.
50. Write about physical properties of liquids.
51. What is liquid crystalline state? Write reasons for existence of the same.
52. What are liquid complexes? Discuss its applications in pharmacy.
53. What are types of liquid crystals? Explain them.
54. Write pharmaceutical applications of liquid crystals.
55. Define the terms
(a) Additive property (b) Constitutive property
(c) Colligative property (d) Refractive index
(e) Molar refraction (f) Optical activity
(g) Specific rotation (h) Dipole moment
(i) Dielectric constant (j) Diamagnetic substance
56. How dipole moment is helpful in elucidation of molecular structure?
57. Explain the terms specific and molar refractivity.
58. Write about induced and orientation polarization.
59. Explain polarimetric measurements.
60. Prove that molar refraction is additive as well as constitutive property.
61. Write note on
(a) Molar refraction (b) Refractive index
(c) Dipole moment (d) Optical rotation
(e) Polarimeter (f) Refractometer
62. Explain the statement “Refractive index decreases with rise in temperature.”
63. What do you mean by the terms – plain polarized light, optically active substance, angle of rotation and molar rotation?
64. Enlist and explain factors on which magnitude of rotation depends for optically active substance.
65. What is difference between polar and non-polar molecule? How the dipole moment of the molecule can be determined?
66. Draw well labelled diagrams of polarimeter and Refractometer.
67. Write applications of following properties in pharmaceutical field.
(a) Refractivity (b) Optical activity
(c) Dipole moment (d) Dielectric constant
(e) X-ray diffraction (f) Light absorption
(g) Dissociation constant