Top 22 Chemistry Interview Questions and Answers (2024)

Here are the most asked basic to advanced level Chemistry interview questions and answers for freshers as well as experienced candidates to get their dream job.

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1) Explain the term Aliquot and Diluent?

  • Aliquot: It is a measured sub-volume of the original sample
  • Diluent: Material with which sample is diluted

2) What is molality?

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

3)  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.

4) What is a buffer?

A buffer is an aqueous solution which has highly stable pH. It is a blend of a weak acid and its conjugate base or vice versa. On adding a small amount of base or acid to buffer, its pH hardly changes.

5) How does buffer work?

In buffer when hydrogen ion is added, it will be neutralized by the base in the buffer.  Hydroxide ion will be neutralized by the acid.  On the overall pH of the buffer solution, these neutralization reactions will not show much effect.

While when you select an acid as a buffer solution, try to use an acid that has a pH closed to your desired pH.  This will help your buffer to achieve a nearly equivalent amount of acid and conjugate base, so that it will enable to neutralize as much as H+ and OH -.

6) 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.

Chemistry Interview Questions
Chemistry Interview Questions

7) How will you calculate how many moles of glucose present in 320 mL of 5.0 M of glucose solution?

First step: Convert the volume from millilitres to litres

  • 320  X (1 litre/1000mL) = 0.320 L solution

Second use the formula = M x V

= 5.0 moles glucose/ litre solution X 0.320 L solution

= 1.6 moles of glucose present in 320mL of solution

8) Explain what is the difference between fractionation and distillation?

Both methods are used to separate the components present in the solution based on the boiling points.

  • Distillation: This technique is used when the boiling point of chemicals are different in the mixtures
  • Fractionation: This technique is used when the boiling point of chemicals are close to each other in the mixtures

9) Mention the formula to calculate pH of a solution?

In order to calculate the pH of a solution you have to use the formula pH= -log [H+] or pH = -log [H3O+]

10) What is the difference between Molarity and Normality?

Both techniques are used to the amount of chemical present in the solution.  However, they are almost similar but differs in

Molarity Normality
Molarity is used to know the total amount of molecules in a 1-liter solution Normality is used to know the total number of reactive units in 1 liter of solution
It is expressed as moles of a compound per litre of solution It is expressed in equivalent per litre

11) 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.

Chemistry Interview Questions
Chemistry Interview Questions

12) Define Avogadro’s law?

According to Avogadro’s law, at the same temperature and pressure, an equal volume of gases contains the same number of molecules regardless of the chemical nature and physical properties.

Avogadro’s number = 6.023 X 1023

13) Explain what makes a molecule into organic molecule?

In a molecule when a hydrogen atom is less than the ratio of the carbon atom, then such molecules are referred to as an organic molecule.


14) Which metal is used to extract copper from the solution of copper sulfate?

Fe or ferrous is the metal that is used to extract copper from the solution of copper sulphate.

15) Explain what is the chemical composition of fat in the human body?

The fat found in the human body is mainly composed of

  • Glycerides
  • Glycerides+Phospholipids
  • Glycolipids
  • Phosphoinositides
  • Tocopherol

16) What is the monomer of polyethylene?

The monomer of polyethylene is ethylene

17) What is the formula you will use to calculate how many milliliters of 5.5 M NaOH are required to prepare 400 mL of 1.5M NaOH?

To know the amount or volume of NaOH to prepare 400 mL of 1.5 M NaOH, we use formula

M1 X V1 = M2 X V2

V1 = M2 X V2/ M1

But before that we will convert 400 mL into litre = 0.4 L

5.5 X V1 = 1.5 M x 0.4 L

V1 = 1.5 M X 0.4L/ 5.5

V1= 0.10 L

V1 = 100mL

So, you need 100mL of 5.5 NaOH

18) Why graphite rod is used in nuclear reactor?

A graphite rod is used in a nuclear reactor allows un-enriched uranium to be used as a nuclear fuel.

19) Mention how many milliliters is equal to 1 liter and how many microliters is equal to liter?

  • 1 millilitre = 0.001 litre
  • 1 microliter = 0.000001 litre

20) 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

Example of oxidation-reduction reaction is observed in the human body when an electron is transferred into the cell and oxidation of glucose take place from which we get the energy.

21) What does iron ore consist of?

Iron ore is consists of Fe2O3

22) Explain what is dextro-rotatory and levorotatory?

Levorotation and Dextrorotation are referred to the properties of plane polarized light when light rotates clockwise when it approaches the observer is then known as dextro-rotation, and when the light rotates anti-clockwise then it is referred as levorotation.

A compound which exhibits a dextro-rotation is referred to as dextro-rotatory and which exhibits levorotation is referred to as levorotatory.

These interview questions will also help in your viva(orals)



  1. Number 19 isn’t correct. 1ml = 0.001L and so on

    1. Avatar Firdous Hanif sayyed says:

      1milliliter =0.0001

      1. 1 millilitre is one 1000th of a litre – therefore 1ml = 0.001L

        1. updated! Thanks for pointing this out

          1. Avatar Vineet Kumar says:

            How to prepare solution in ppm

    2. Avatar Madhuri Ingale says:

      Avogadro’s no is wrong it is 10^+23

      1. Avatar Muthu srp Gowda says:

        That’s also correct it is 6.023×10^23

    3. Avatar Surekha Moin says:

      Very basically important question answer

    4. Avatar Poojavaddi says:

      Yes it’s right 1ml=0.001L Due to it’s A conversion factor form Milli liters to liters i.e (1/1000 of liter)

    5. Avatar Nice question thanks says:

      Nice question

    6. What’s the difference in your answer and above que.19th answer??😁

  2. How can we determine the boiling points of components in the mixture are far or close to each other?

    1. How can u determine the rectified spirit

        1. what is the modern name of element ”sb” ???

          1. stibnite/antimony

          2. Avatar Vishal mali says:


    2. Avatar Sagar patel says:

      By fractional distillation or extractive distillation

      1. Avatar Aklesh singh says:

        Fractional distillation is a process of separating a mixture of chemical compounds.

    3. Avatar Chandini chandu says:

      By using ditillation metgod first smaller boiling point will come first then tha second comes

      1. Avatar Aklesh singh says:

        If the difference in boiling points of two liquid is not much, fractional distillation is used to separate them. In this technique, fractionating column is fitted over the mouth of the round bottom flask.
        When vapours of a liquid mixture are passed through a fractionating column, the capours of the low boiling liquid (A) will move up while those of the high boiling liquid will condense and fall back into the flask. Therefore, liquid (A) with low boiling point will distill first.

    4. Avatar says:

      The ones that are more volatile evaporate fasts

  3. Avatar kundan kumar says:

    Practicle questions chemistory

  4. How to make M/10 solution

    1. Dilute solution with 100ml distilled water

    2. Avatar Aklesh singh says:

      Its molecular mass is 106. To prepare \frac{M}{10} Na2CO3 solution, 10.6 g of sodium carbonate should be dissolved per litre of the solution. Normally in the laboratory we are required to prepare 250 ml of solution.

  5. Avatar Santhosh chitti says:

    Nice qutions

  6. Usefull questions …thnk u for give this questions..

    1. Avatar Zulfiqar Ali says:

      Yes very useful

  7. Avatar Sakthynivedha says:

    Pls join ts Grp. Very nice and good

  8. What is range of water

  9. Avatar Chetan Bagora says:

    Very useful questions. thanks

  10. Avatar Gopabandhu Majhi says:

    calculate repulsive force between two electron? when the distance between then is 4.10* -15 (four into ten two the power -15?

  11. Avatar Murugesan.p says:

    good in improview the knowledge questions.

  12. What is Balance shell????

    1. Very useful .what is valance shell

      1. a place outside the nucleus where an electron can move around the nucleus

  13. Useful questions. but check your answer on question 19.

    1. updated! Thanks for pointing this out

  14. Avatar Sandeepreddy says:

    Please provide more questions

  15. Avatar Azim Ghanchi says:

    Excellent performance for Interview questions once again inter questions basic level

  16. Avatar Abrham mengstu says:

    I am Abrham and I am learning an industrial chemistry in undergraduate level so I want to learn master through fast track. So to get this opportunity there is an interview, please help to answer the interview questions

  17. Avatar Sandeep Kamble says:

    I am chemistry student learn about in chemistry

  18. Avatar M. Naveenkumar says:

    Thank you for google, it gave top 22 chemistry interview questions

  19. A microlitre is 10-^6 of a litre. It should read 0.000001L

    1. Thanks for writing. It is updated.

  20. Nice….. Do you have more questions…??

  21. PLS more interview questions on clinical chemistry

  22. Avatar Prashant lad says:

    Thnx…..Very important questions

  23. Avatar Prashant lad says:

    What is mean by pH

    1. Avatar Nilesh tripathi says:

      Potential of hydrogen

  24. Avatar Routhu Jagadeesh says:

    Please provide 3years experience interwe qoustions

  25. Avatar Parthiban says:

    I ma bsc chemistry I am completely 2108 batch but freshers student

  26. Avatar Ankita Vishal Kadam says:

    More important questions and answers plz

  27. Really… Very useful

  28. Avatar Ambarish Nalatawad says:

    Usefull questions….tq

  29. Avatar Harkesh Raut says:

    What is water properties…?

  30. Avatar Swaraj jadhav says:

    Plz noted That
    If 1 ml = 0.001 litre
    Then 1microlitre= 0.001 ml hence it is 0.000001 litre

    1. Thanks for writing. It is updated.

  31. Avatar yobsan abdena says:

    i appritiate it thunks

  32. Is is useful to freshers also

  33. Avatar Dinesh tulshiram Mistari says:

    Pls provide more videos…its very helpful

  34. Sir i have done masters in chemistry but sir i want to clear all basic

  35. In 19th question Maybe 1microliter will be 0.000001

    1. Thanks for pointing out. It is updated.

  36. Avatar Marmat bhagyashri motilal says:

    Give more Question for interview

  37. Avatar Musrath Jahan says:

    Am Musrath Jahan, will have to attend content writing chemistry exam for 11th and 12 grade need specimen copy of question and answer script.

    Thank you.

  38. Avatar Azhar mahmood says:

    Very important information

  39. Give more questions for interview

    1. Avatar Gedda Venkatesh says:

      Interview questions and answers

  40. Avatar Kampe sandeep says:

    I need some more information by giving the definitions with formula
    Because is to learn with interest

  41. Avatar Niranjan Talange says:

    Please provide more basic questions

  42. Avatar Pagire Ramdas V. says:

    Give more questions related with Msc chemistry Syllabus.

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  45. Avatar Himanshi kanojiya says:

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    1. Avatar Mahima Dilip Patil says:

      Chemistry definition

  46. Avatar Kotoku Caleb says:

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  48. I really appreciate this, PLS more basic questions for interview for nursing, will nmombum@

  49. Avatar All questions are nice but there is a mistake in 12th question. The value of avagadro no is 6.023×10^23 not 10^-23 says:

    All questions are nice but there is a mistake in 12th question. The value of avagadro no. 6.023×10^23 not 10^-23

    1. Hi,

      Thanks for writing. It is reviewed.

  50. Avatar Mahima Dilip Patil says:

    Chemistry definition

    1. Avatar Badgujar Mohan says:

      Study of physical and chemical properties

  51. Question no 8 there is small mistake in ans. Use of distillation and fractionation (1st sentence) .

    1. Alex Silverman Alex Silverman says:

      It is corrected..!!

  52. Avatar Sunpharma company says:

    Quilaty control,pharma jobs

  53. Avatar Vishal Yadav says:

    Must important Questions that’s really necessary for an Interview all questions come from basic chemistry and must know if you are a student of chemistry subject

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