Рhysical and colloidal chemistry

Питання 1

What phases are in equilibrium at the eutectic point of the melting diagram of a mixture of menthol and camphor that can be used as a solvent for some medicinal substances that are poorly soluble in water?

Inclusions of large camphor crystals in a fine mixture of menthol crystals

Crystals of a chemical compound that formed as a result of interaction between menthol and camphor

Inclusions of large menthol crystals in a fine mixture of camphor crystals

Water, menthol crystals, camphor crystals

Eutectic melt, menthol crystals, camphor crystals

Питання 2

In production of pharmaceutiсals, compounds that increase the stability of medicines play an important role. Surfactants and are used to increase the stability of concentrated emulsions and prevent their stratification are called:

Solubilizers

Peptizers

Activators

Coagulators

Emulsifiers

Питання 3

What happens with the osmotic pressure of a surfactant solution after the critical micelle concentration (CMC) is reached?

It remains unchanged

It begins to increase rapidly

The dependence of the osmotic pressure on the concentration within the range of C>CMC is the same as within the range of C

It begins to decrease rapidly due to the process of micelle formation

It stops increasing and remains practically unchanged or increases very slightly

Питання 4

On which parameter does coagulation capability of an electrolyte depend?

Degree of sol dispersion

Electrolyte concentration

Charge of the coagulating ion

Sol density

Sol volume

Питання 5

Sedimentation is characteristic of which type of systems?

Sols

Suspensions

Non-electrolyte solutions

Electrolyte solutions

Solutions of high molecular substances

Питання 6

Thermal analysis is used in pharmacy to identify drugs and determine drug purity. What coordinates are necessary to build a cooling curve?

Pressure-time

Volume-temperature

Temperature-volume

Volume-time

Temperature-time

Питання 7

Catalysts are widely used in production of drugs. How can reaction acceleration in the presence of a catalyst be explained?

Activation energy decreases

Collision frequency decreases

Total collision frequency increases

Activation energy increases

Molecule speed increases

Питання 8

Synthesis of a medicinal substance occurs in an isolated system. What is a direction criterion of spontaneous processes?

Enthalpy

Entropy change

Intrinsic energy

Helmholtz energy

Gibbs energy

Питання 9

Surfactants are compounds that lower the surface tension (or interfacial tension) between two liquids, between a gas and a liquid, or between a liquid and a solid. Which of the following substances exhibits the properties of a surfactant at the air-water interface?

NaOH

Urea

HCl

Valeric acid

-

Питання 10

In order to facilitate usage and achievement of necessary therapeutic effect, the drug or medicinal plant material is given a certain dosage form. Indicate the dosage form in the form of a free-disperse system:

Jelly

Membrane

Emulsion

Diaphragm

Gel

Питання 11

In the pharmaceutical company,without setting up an experiment, the researcher calculated the expected termal effects of the chemical reaction. What properties determine the possibility of such calculation in accordance with the Hess law?

Process duration

Number of intermediate stages

Route by which the chemical change occurs

Initial and final state of system

Mechanism by which the chemical change occurs

Питання 12

Name the structural unit of a colloidal solution of a medicinal substance:

Zwitterion

Atom

Ion

Micelle

Molecule

Питання 13

Name the process of spontaneous adhesion of drops in an emulsion to each other:

Sedimentation

Coalescence

Flotation

Flocculation

Coagulation

MDstuds

MDstuds

Рhysical and colloidal chemistry