1. Phase diagram is a graphical representation of the ________ states of a substance under different conditions of temperature and pressure.
a) physical
b) chemical
c) electromagnetic
d) mechanical
Discussion
Explanation: Phase diagram is a graphical depiction of the physical conditions of a matter under different conditions of temperature and pressure. It has temperature on the x-axis and pressure on the y-axis.
2. __________ diagrams represent the phase behavior of mixtures containing three components.
a) Ternary phase
b) Tertiary phase
c) Tri phase
d) Term phase
Discussion
Explanation: The ternary phase represents the behavior of three components in a mixture with a triangular diagram. These diagrams provide the data which is precise and accurate of the various components.
3.The effect of ______on the system is seen only as a phase change.
a) Latent heat
b) Specific heat
c) Enthalpy
d) Entropy
Discussion
Explanation: Latent heat can be defined as the heat that is released or absorbed by a system during constant temperature process. The effect is seen only as a phase change like boiling of water or the melting of ice.
4. What is the critical point of water?
a) 374°C
b) 157.5°C
c) 31.0°C
d) 240.9°C
Discussion
Explanation: The critical point of water is 374°C. The critical point of sulphuric acid is 157.5°C. The critical point of supercritical carbon dioxideis 31.0°C. The critical point of ethanol is 240.9°C.
5. _____________ is the amount of moisture a material will absorb relative to ambient temperature and humidity conditions.
a) Lyophilization
b) Hygroscopic action
c) Hydrophobic action
d) Hydrophilic action
Discussion
Explanation: Hygroscopic action is the amount of moisture a material will absorb with respect to the temperature and humidity conditions. Due to hydroscopic action, the sample will continuously increase/ decrease in weight.
6. Halogen and infrared drying are the examples of _________________
a) thermogravimetric analysis
b) freeze drying
c) non thermal analysis
d) pressure based analysis
Discussion
Explanation: Halogen and infrared drying are the examples of thermogravimetric analysis. Halogen drying is up to twice as fast as traditional infrared technology. It is a complete, precise and approachable method to determine moisture.
7. The oven drying methodology consists of heating by ________
a) conduction
b) convection
c) radiation
d) both radiation and convection
Discussion
Explanation: The most commonly used method for commercial purposes is oven drying methods for commercial purposes. The oven drying methodology consists of heating by convection. The demerits of this process are time and non-portability.
8. ______________ of moisture measurement is based on chemical reactions.
a) Lyophilization
b) Karl Fischer method
c) Halogen drying
d) Infrared drying
Discussion
Explanation: Karl Fischer Method of moisture measurement is based on chemical reactions. A chemical reaction happens where the water is separated chemically from the rest of the sample. The water is then moved to other cell where it is measured. That measurement is equated with the initial mass of the sample and then moisture content is calculated.
9. _________ method id based on dielectric principle.
a) Electric moisture meter
b) Karl Fischer method
c) Lyophilization
d) Infrared drying
Discussion
Explanation: Electric moisture meter method id based on dielectric principle. The electricity is measured by capacitance, conductance and radio frequency. They are inexpensive, easy to use and portable.
10. __________ uses reflectance & absorbance principles for calculating the moisture content.
a) Karl Fischer method
b) Nuclear moisture meter method
c) Loss on drying moisture meter method
d) Near infrared moisture meter method
Discussion
Explanation: Near infrared moisture meter method uses absorbance and reflectance principles for determining the moisture content. This meter focuses a beam of light on the product and then the light is filtered to a wavelength that excites the moisture molecules. The higher the amount of moisture content, higher is the amount of light absorbed.