400+ Research Associate Interview Questions and Answers

Aldol condensation, Michael addition, Wittig reaction, Grignard reaction are some name reactions to form new c-c bond without metal catalyst.

• Aldol condensation involves the reaction of an enolate ion with an aldehyde or ketone to form a β-hydroxy carbonyl compound.

• Michael addition involves the addition of a nucleophile to an α,β-unsaturated carbonyl compound.

• Wittig reaction involves the reaction of a phosphorus ylide with an aldehyde or ketone to form an alkene.

• Grignard react...read more

To separate acid from an acid-base mixture in liquid state, we can use various methods such as solvent extraction, distillation, or ion exchange.

• Solvent extraction involves adding a solvent that selectively dissolves the acid, then separating the two layers.

• Distillation involves heating the mixture to vaporize the acid, then condensing it back into a separate container.

• Ion exchange involves passing the mixture through a resin that selectively binds to the acid, then eluting t...read more

I would investigate the cause and try alternative sterilization methods.

• Check if there is an issue with the equipment or the sterilization process

• Try alternative sterilization methods such as chemical sterilization or dry heat sterilization

• Consult with colleagues or experts in the field for advice

• Document the issue and any actions taken for future reference

NMR stands for Nuclear Magnetic Resonance. It is a spectroscopic technique used to study the magnetic properties of atomic nuclei.

• NMR works by applying a strong magnetic field to a sample and then measuring the absorption and emission of electromagnetic radiation by the nuclei in the sample.

• It is used in chemistry to determine the structure and composition of molecules, as well as to study chemical reactions.

• In medicine, NMR is used in magnetic resonance imaging (MRI) to prod...read more

I would choose to follow safety parameters over GLP.

• Safety of personnel and environment is of utmost importance

• GLP can be compromised temporarily but safety cannot

• Non-compliance with safety regulations can lead to serious consequences

Rest ethyl acetate in compound can be found by NMR using specific peaks and chemical shifts.

• Look for the peak at 1.0-1.2 ppm which corresponds to the ethyl group

• Look for the peak at 4.0-4.1 ppm which corresponds to the acetate group

• Subtract the integral of these peaks from the total integral to find the rest ethyl acetate

• Compare the chemical shifts of the peaks to known values for ethyl acetate

Column and mobile phase selection is based on the analyte properties and separation goals.

• Consider the analyte's physicochemical properties such as polarity, molecular weight, and stability.

• Choose a column with appropriate stationary phase chemistry (e.g., C18 for hydrophobic compounds).

• Optimize mobile phase composition (solvent ratio, pH, buffer) for desired separation.

• Consider the separation goals (resolution, selectivity, speed) and adjust column and mobile phase according...read more

Answering questions related to upstream processing, including process flow, material and system use, FIT, CIP, SIP, bioreactor system, and role of raw material in media.

• Previous job responsibilities in upstream processing

• Process flow of upstream processing

• Make and MOC of the material and system use during operation

• FIT, CIP, and SIP

• Types of and part of bioreactor system

• Role of raw material in media

The desired product of bromination on aniline is 2,4,6-tribromoaniline. The desired product of bromination on toluene is bromotoluene.

• Bromination on aniline results in the substitution of three bromine atoms on the aromatic ring, yielding 2,4,6-tribromoaniline.

• Bromination on toluene results in the substitution of one bromine atom on the aromatic ring, yielding bromotoluene.

H1NMR values are chemical shifts observed in nuclear magnetic resonance spectroscopy. NMR is a technique used to study the structure and properties of molecules.

• H1NMR values refer to the chemical shifts observed in proton nuclear magnetic resonance spectroscopy.

• NMR is a powerful analytical technique used to study the structure, dynamics, and properties of molecules.

• It involves the interaction of atomic nuclei with a strong magnetic field and radiofrequency radiation.

• Different...read more

Pyrophoric chemicals can be handled and quenched by using inert gases, specialized containers, and proper disposal methods.

• Use inert gases such as nitrogen or argon to displace air and prevent ignition.

• Store and handle pyrophoric chemicals in specialized containers such as air-tight glass ampoules or sealed metal containers.

• Dispose of pyrophoric chemicals properly by contacting a hazardous waste disposal company.

• Examples of pyrophoric chemicals include alkali metals, metal hy...read more

Glycerol is used for long term preservation of bacterial cultures due to its ability to prevent ice crystal formation and cell damage.

• Glycerol acts as a cryoprotectant, preventing ice crystal formation and cell damage during freezing.

• It allows for long term storage of bacterial cultures at -80°C.

• Glycerol is added to the bacterial culture before freezing to a final concentration of 15-20%.

• It is a common practice in microbiology and biotechnology research.

• Other cryoprotectants ...read more

Esters can be converted to aldehydes by hydrolysis under acidic conditions.

• Esters can be hydrolyzed to aldehydes using a strong acid, such as sulfuric acid or hydrochloric acid.

• The reaction involves the cleavage of the ester bond and the formation of a carboxylic acid intermediate, which is then further reduced to an aldehyde.

• The reaction can be carried out at elevated temperatures or using a catalyst, such as p-toluenesulfonic acid.

• For example, ethyl acetate can be converted...read more

To prepare 0.1 N HCl and NaOH, you need to calculate the required amount of the respective chemicals and dilute them in water.

• Calculate the molar mass of HCl and NaOH

• Determine the volume of solution needed

• Use the formula: Normality (N) = (Number of equivalents / Volume of solution in liters)

• For 0.1 N HCl, calculate the number of equivalents of HCl and dilute it to the desired volume

• For NaOH, calculate the number of equivalents of NaOH and dilute it to the desired volume

• Always...read more

The Grignard reaction on an aldehyde will produce a secondary alcohol.

• The Grignard reaction involves the addition of a Grignard reagent (organomagnesium compound) to an aldehyde or ketone.

• The reaction proceeds through the formation of a carbon-carbon bond.

• In the case of an aldehyde, the product will be a secondary alcohol.

• For example, the reaction of formaldehyde (HCHO) with a Grignard reagent such as methylmagnesium bromide (CH3MgBr) will yield isopropyl alcohol (CH3CH(OH)CH...read more

The molecule can be converted into another molecule using reducing or oxidizing agents.

• Identify the functional groups present in the molecule

• Choose a suitable reducing or oxidizing agent based on the functional groups

• Perform the reaction under appropriate conditions

• Isolate and purify the product

• Examples: converting a ketone to an alcohol using NaBH4 as a reducing agent, converting an alcohol to a ketone using PCC as an oxidizing agent

The choice of solvent can affect the UV spectrum by shifting the absorption peaks and changing the intensity.

• Solvents with different polarities can affect the UV spectrum differently.

• Solvents can cause shifts in the absorption peaks due to changes in the electronic environment.

• Solvents can also affect the intensity of the absorption peaks.

• The choice of solvent should be carefully considered to ensure accurate and consistent results.

• For example, water can cause shifts in the U...read more

Various company sources are used to give ESG risk ratings.

• Company reports and disclosures

• Third-party data providers

• News articles and media coverage

• Industry benchmarks and standards

• Stakeholder engagement and surveys

Chromatography is a technique used to separate and analyze mixtures. HPLC is a type of chromatography used for high-resolution separation.

• Chromatography involves passing a mixture through a stationary phase, which separates the components based on their properties.

• HPLC uses high pressure to force the mixture through a column packed with a stationary phase, allowing for more precise separation.

• HPLC is commonly used in pharmaceuticals, forensics, and environmental testing to an...read more

pKa, LogP, and method development validation parameters are important in research associate work.

• pKa is a measure of acid strength and is important in drug design.

• LogP is a measure of lipophilicity and helps predict drug absorption and distribution.

• Method development validation parameters ensure accuracy and reliability of analytical methods.

• Examples of validation parameters include specificity, accuracy, precision, and linearity.

• These parameters are necessary to ensure the q...read more

Spectroscopy is the study of interaction between matter and electromagnetic radiation. UV spectroscopy measures absorption of UV light.

• Spectroscopy is used to identify and quantify substances based on their interaction with light.

• UV spectroscopy measures the absorption of UV light by molecules in a sample.

• UV spectroscopy is commonly used in the analysis of organic compounds.

• The range of UV spectroscopy is typically between 190-400 nm.

• UV spectroscopy can be used to determine t...read more

Reagents used in Suzuki coupling

• Palladium catalyst (e.g. Pd(PPh3)4)

• Organoboron compound (e.g. arylboronic acid)

• Base (e.g. potassium carbonate)

• Solvent (e.g. DMF, toluene)

I have experience handling various oxidation and reduction reagents in my previous research work.

• I have worked with common oxidizing agents such as potassium permanganate, hydrogen peroxide, and chromic acid.

• I have also handled reducing agents like sodium borohydride, lithium aluminum hydride, and diisobutylaluminum hydride.

• I am familiar with the safety precautions and proper handling techniques for these reagents.

• I have used these reagents in various chemical reactions to sy...read more

Recombinant fermentation is a process of using microorganisms to produce recombinant proteins.

• Recombinant DNA technology is used to insert a gene into a microorganism's DNA

• The microorganism is then grown in a fermentation tank to produce the desired protein

• Examples include the production of insulin using E. coli bacteria

• Optimization of fermentation conditions is crucial for high yield and purity of the protein

Apart from Google, I would verify the background of a company by checking their financial statements, news articles, and industry reports.

• Check financial statements for revenue growth and profitability

• Read news articles for any controversies or legal issues

• Review industry reports for market trends and competition

• Check social media and online reviews for customer satisfaction

• Contact former employees or industry experts for insider information

Interpretation of NMR with coupling constant

• Coupling constant is the distance between two peaks in a multiplet

• It indicates the number of neighboring protons

• The coupling constant can be used to determine the stereochemistry of a molecule

• The coupling constant can also be used to determine the hybridization of a carbon atom

• The magnitude of the coupling constant depends on the strength of the spin-spin coupling

• A doublet has a coupling constant of around 7 Hz, a triplet around 7-9...read more

SDS (sodium dodecyl sulfate) is a detergent used in SDS-PAGE to denature proteins and impart a negative charge for separation.

• SDS denatures proteins by disrupting non-covalent bonds, leading to linearization.

• It imparts a uniform negative charge to proteins, allowing separation based on size.

• In SDS-PAGE, smaller proteins migrate faster through the gel than larger ones.

• Example: In a protein mixture, SDS-PAGE can separate enzymes from structural proteins based on their molecular...read more