L3 - Drying

Drying in the pharmaceutical industry can be used to achieve which of the following?

• Increase the bulk of the product

• To increase the chemical reactivity of the remaining water

• To facilitate particle size reduction

• To increase the weight of the end product to assist with storage

Which of the following statements are TRUE with regard to the rate of drying?

• In the initial adjustment stage (AB), the rates of cooling and heating become equal

• In the initial adjustment stage (AB), as the moisture from the solid evaporates, the temperature increases

• At Point C (Critical Moisture Content), dry spots are formed in the interior of the solids

• In the first falling rate (CD) period, the rate of drying falls more rapidly than the second falling rate (DE)

Which of the following statements are TRUE? Select ALL that apply

• When the dried material is friable, a suitable dryer is one that produces excessive agitation

• Vacuum tumble and Turbo-tray are examples of dryers that can be used for dried products that will be milled

• Microwave dryers are rarely used as they are not energy efficient

• Cake filtration is where the recover of solids are desired

Becomes more fluid when stirred faster. Which term does this describe?

• Plasticity

• Pseudoplasticity

• Dilatancy

• Neuroplasticity

Which of the following describes non-Newtonian fluids?

• Examples include water and ethanol

• Stirring action will not change the viscosity

• Viscosity does not remain constant

• Viscosity is independent of stress