Top 10 Chemistry Interview Questions and Answers (2023)

1.What is general chapter balance

TWO general chapter

1) USP41 2) USP1251

2. What is EDQM full from

European Directorate for the Quality of Medicines & HealthCare.

3. HPLC vial size and how much injection taken?

2 ml vial and 800 micro liter Injection taken hplc

4. Analytical Method validation chapter No

Chapter  no <1225>

5. What is RT and RRT in HPLC?

RT means Retention time

RRT means Relative Retention time

Relative retention time mean as compared main peak

Example Main peak RT is 5 and A impurities RT is 2

So RRT =2/5 =0.4

Impurities A RRT =0.4

6. What is molality?

Molality is the number of solutes that are present in 1 kg of a solvent.

7. What is titration?

Titration is a process to determine the molarity of a base or an acid.  In this process, a reaction is carried out between the known volumes of a solution with a known concentration, against the known volume of a solution with an unknown concentration.

8.What is a mole?

Mole is the unit used to define the number of chemical substance present in a substance. It is the amount of substance which consists of the same number of chemical units as there are atoms in exactly 12 gram of pure carbon-12.

9.What is Valency?

Valency is a property of groups or atoms, equal to the number of atoms of hydrogen that the group or atom could combine with or displace it in forming compounds.

10. What is the monomer of polyethylene?

The monomer of polyethylene is ethylene

11. What is oxidation and reduction reaction?

• Oxidation = When there is a loss of hydrogen or electrons OR gain of oxygen is known as Oxidation reaction.
• Reduction = When there is a gain of hydrogen or electron OR loss of oxygen is known as a reduction reaction

12. What is ph definition

Negative log H+ Concentration

13. What is Stomach  pH ?

about pH 6

 

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