40+ Interview Questions and Answers

HPLC is a technique used to separate, identify, and quantify components in a mixture. UV detection is commonly used in HPLC to measure analyte concentration.

• HPLC stands for High-Performance Liquid Chromatography.

• It uses a liquid mobile phase and a solid stationary phase to separate components based on their interactions with the stationary phase.

• UV detection in HPLC involves measuring the absorbance of UV light by the analyte.

• UV detectors are commonly used because many compou...read more

Overhead rate for Inventory valuation is calculated by dividing total overhead costs by total direct labor hours. Inventory valuation methods include FIFO, LIFO, and weighted average. CAS 4 deals with depreciation accounting. CAS applicable in current company may vary. Good knowledge in MS Excel is essential. COP is the cost of producing goods, while COGS is the cost of goods sold.

• Calculate overhead rate by dividing total overhead costs by total direct labor hours

• Inventory va...read more

QC Person ensures products meet quality standards by conducting tests and inspections.

• Conducting tests and inspections on raw materials, in-process samples, and finished products

• Documenting and reporting test results

• Identifying and addressing quality issues

• Ensuring compliance with regulatory requirements

• Collaborating with other departments to improve product quality

• Maintaining and calibrating laboratory equipment

• Training and mentoring other employees

• Examples: QC chemist in ph...read more

Temperature calibration of a thermometer

• Calibration involves comparing the thermometer readings to a known standard

• Adjustments are made to the thermometer if there are any discrepancies

• Calibration is important to ensure accurate and reliable temperature measurements

• Examples of standards used for calibration include NIST-traceable thermometers and ice-point method

Major breakdowns in reactor, centrifuge, and ANFD and their solutions.

• Reactor breakdown: Possible causes include overheating, loss of coolant, or control system failure. Solutions may involve emergency shutdown, cooling measures, or repairs.

• Centrifuge breakdown: Common issues include imbalance, bearing failure, or motor malfunction. Solutions may include recalibration, replacement of faulty parts, or maintenance.

• ANFD breakdown: Problems can arise from clogging, leakage, or ma...read more

Reactors may face various types of problems, and they can be rectified through troubleshooting and maintenance.

• Reactors may face issues such as overheating, leaks, or mechanical failures.

• To rectify these problems, troubleshooting techniques can be used to identify the root cause.

• Maintenance activities like cleaning, repairing, or replacing faulty components can help in resolving the issues.

• Regular inspections and preventive maintenance can prevent problems from occurring in t...read more

Sulfated ash refers to the inorganic residue left behind after a substance is burned at high temperatures.

• Sulfated ash is a measure of the inorganic content of a substance.

• It is determined by burning a sample of the substance and measuring the residue.

• The residue consists of minerals and other inorganic compounds that do not burn.

• Sulfated ash is commonly used in the analysis of lubricants and petroleum products.

• It helps determine the level of impurities and contaminants in th...read more

Changing mechanical seal pumps and reactors involves several steps and precautions.

• Ensure the pump or reactor is properly shut down and isolated from the power source.

• Drain the fluid from the pump or reactor and relieve any pressure.

• Remove the old mechanical seal carefully, following the manufacturer's instructions.

• Clean the seal chamber and inspect for any damage or wear.

• Install the new mechanical seal, ensuring proper alignment and tightness.

• Reassemble the pump or reactor, ...read more

Analytical method validation involves testing and verifying the accuracy and reliability of a method for analyzing a sample.

• Define the purpose and scope of the method

• Select appropriate analytical parameters

• Conduct method development and optimization

• Perform method validation experiments

• Document and report results

• Repeat validation periodically

• Examples: HPLC, GC, titration, spectrophotometry

UV detects conjugated systems, IR detects functional groups, NMR detects chemical environment

• UV detects conjugated systems such as double bonds and aromatic rings

• IR detects functional groups such as carbonyl and hydroxyl groups

• NMR detects the chemical environment of atoms in a molecule

• Examples include using UV to detect the presence of a double bond in a molecule, using IR to identify the functional groups in a compound, and using NMR to determine the structure of a molecule

Pharmaceutical companies are businesses that research, develop, manufacture, and market drugs and medical devices.

• Pharmaceutical companies are involved in the research and development of new drugs and medical devices

• They manufacture and market drugs and medical devices

• They are regulated by government agencies such as the FDA

• Examples of pharmaceutical companies include Pfizer, Johnson & Johnson, and Merck

Titrations are analytical techniques used to determine the concentration of a substance in a solution by reacting it with a known volume and concentration of another substance.

• Types of titrations include acid-base titrations, redox titrations, and complexometric titrations.

• Procedures involve adding a titrant (solution of known concentration) to the analyte (solution of unknown concentration) until the reaction is complete.

• Methods include using indicators to determine the endp...read more

Choosing columns for analytical methods

• Consider the analyte properties and selectivity of the column

• Choose a column with appropriate dimensions and particle size

• Evaluate the compatibility of the column with the sample matrix

• Consider the cost and availability of the column

• Perform method validation to ensure column suitability

Calibration parameters are variables used to adjust or fine-tune a system or instrument to ensure accuracy and reliability.

• Calibration parameters are used to adjust or align measurements to a known standard.

• They are typically specific to the system or instrument being calibrated.

• Examples of calibration parameters include gain, offset, linearity, and sensitivity.

• Calibration parameters can be adjusted manually or automatically.

• Regular calibration is important to maintain the ac...read more

Chromatography is a technique used to separate and analyze mixtures of chemicals.

• It involves a stationary phase and a mobile phase

• The sample is introduced into the mobile phase and travels through the stationary phase

• Different components of the sample interact differently with the stationary phase, causing them to separate

• Common types include gas chromatography, liquid chromatography, and ion chromatography

Validation parameters are criteria used to ensure that data or processes meet certain standards or requirements.

• Validation parameters can include accuracy, completeness, consistency, and timeliness.

• For example, in data entry, validation parameters may include checking for correct formatting, required fields, and valid values.

• In software development, validation parameters may include testing for functionality, usability, and security.

• Validation parameters can also be used in m...read more

Spectroscopy is the study of the interaction between matter and electromagnetic radiation.

• It involves the use of various instruments to measure and analyze the absorption, emission, or scattering of light by a sample.

• It is used in various fields such as chemistry, physics, astronomy, and biology.

• Examples include UV-Vis spectroscopy, infrared spectroscopy, and nuclear magnetic resonance spectroscopy.

• It can be used to identify and quantify the components of a sample, determine ...read more

Region of UV, IR and NMR are specific ranges of electromagnetic radiation used for spectroscopic analysis.

• UV region is from 10-400 nm and is used for determining the electronic structure of molecules.

• IR region is from 4000-400 cm-1 and is used for determining the functional groups present in a molecule.

• NMR region is from 0-10 ppm and is used for determining the chemical environment of atoms in a molecule.

• Each region provides unique information about the molecule being analyze...read more

Assay in drug substance is a test used to determine the potency or concentration of a drug in a sample.

• Assay is a quantitative analysis method used to measure the amount of a specific substance in a sample.

• It is commonly used in pharmaceutical industry to ensure the quality and consistency of drug products.

• Assay results are compared to a standard reference to determine the potency or concentration of the drug.

• Examples of assays include HPLC (High Performance Liquid Chromatogr...read more

Reactions are chemical processes that involve the transformation of one or more substances into new substances.

• Combustion: a reaction between a fuel and an oxidant that produces heat and light (e.g. burning of wood)

• Acid-base: a reaction between an acid and a base that produces water and a salt (e.g. reaction between hydrochloric acid and sodium hydroxide)

• Redox: a reaction in which there is a transfer of electrons between reactants (e.g. rusting of iron)

• Polymerization: a react...read more

Alcoa stands for Analytical Laboratory Control on Arrival, a process used in the pharmaceutical industry to ensure the quality of raw materials.

• Alcoa is a set of guidelines used to ensure data integrity in pharmaceutical manufacturing.

• It stands for Attributable, Legible, Contemporaneous, Original, and Accurate.

• Alcoa principles are used to ensure the reliability and accuracy of data in pharmaceutical testing and analysis.

• For example, ensuring that all data is attributable to a...read more

The current Ctc and major expectation are important factors in determining the candidate's salary and career goals.

• The current Ctc refers to the candidate's current salary or compensation package.

• Major expectation refers to the candidate's primary career goals or desired outcomes from the job.

• These factors help in assessing the candidate's fit for the role and aligning expectations.

• Example: Current Ctc - $60,000 per annum, Major expectation - Career growth and learning opport...read more

The boiling points of solvents vary depending on their chemical properties.

• Boiling point is the temperature at which a solvent changes from a liquid to a gas.

• Different solvents have different boiling points due to variations in their molecular structures.

• Boiling points can be influenced by factors such as intermolecular forces and molecular weight.

• Examples of solvents and their boiling points include water (100°C), ethanol (78.37°C), and acetone (56.05°C).

The question is unclear and lacks context. Please provide more information.

• The question needs to be more specific about what it means by 'companies changes'

• It would be helpful to know the industry or sector being referred to

• Without more information, it is impossible to provide an accurate answer

The Safety Triangle is a concept used in occupational safety to illustrate the three key elements of safety: engineering, education, and enforcement.

• The Safety Triangle emphasizes the importance of engineering controls, such as safety equipment and machinery safeguards, in preventing accidents.

• Education plays a crucial role in promoting safety awareness and providing training to employees on safe work practices.

• Enforcement involves implementing and enforcing safety policies, ...read more

Method precision refers to the consistency of results obtained from the same method, while system precision refers to the consistency of results obtained from different methods or instruments.

• Method precision is important for ensuring the reliability of a single method or instrument.

• System precision is important for ensuring the comparability of results obtained from different methods or instruments.

• The difference between method precision and system precision can impact the a...read more

IR values of functional groups indicate the presence of specific bonds in a molecule.

• IR values are unique for different functional groups, allowing for identification in a molecule

• Common IR values include 3300-3500 cm^-1 for O-H stretch in alcohols, and 1700-1750 cm^-1 for C=O stretch in carbonyl compounds

• IR spectroscopy is a valuable tool in organic chemistry for structural determination

Assay formula is a specific calculation used to determine the concentration or purity of a substance in a sample.

• Assay formula typically involves measuring the amount of a specific compound or molecule in a sample.

• It may involve using a standard curve to determine the concentration of the substance.

• Assay formulas can vary depending on the type of assay being performed, such as ELISA or PCR.

• Examples include calculating the protein concentration in a sample using a Bradford ass...read more

Standard agreement formula is a legally binding document outlining terms and conditions agreed upon by parties involved.

• Include names and signatures of all parties involved

• Clearly outline the terms and conditions of the agreement

• Specify the duration of the agreement

• Include clauses for termination and dispute resolution

• Ensure the agreement is legally binding and enforceable

Distillation types include simple distillation, fractional distillation, and vacuum distillation.

• Simple distillation is used to separate liquids with different boiling points.

• Fractional distillation is used to separate liquids with similar boiling points.

• Vacuum distillation is used to separate liquids with high boiling points or heat-sensitive compounds.

Grid and distribution system refers to the network of power lines and equipment used to deliver electricity from power plants to consumers.

• Grid system refers to the interconnected network of power plants, substations, and transmission lines used to transmit electricity over long distances.

• Distribution system refers to the network of power lines, transformers, and other equipment used to deliver electricity from the grid to homes and businesses.

• Grid system operates at high vol...read more

Safety refers to the measures taken to prevent accidents, injuries, and hazards in order to protect individuals and promote well-being.

• Safety involves identifying and assessing potential risks and hazards in the workplace or environment.

• It includes implementing preventive measures such as safety protocols, training programs, and safety equipment.

• Safety also involves promoting a safety culture and ensuring compliance with safety regulations and standards.

• Examples of safety mea...read more

LEL stands for Lower Explosive Limit and UEL stands for Upper Explosive Limit.

• LEL is the lowest concentration of a flammable substance in air that can ignite and sustain combustion.

• UEL is the highest concentration of a flammable substance in air that can ignite and sustain combustion.

• Concentrations below LEL are too lean to burn, while concentrations above UEL are too rich to burn.

• Knowing LEL and UEL helps in determining safe working conditions and preventing explosions.

• For e...read more

I am responsible for ensuring the quality of products through analysis and testing.

• Performing quality control tests on raw materials, in-process samples, and finished products

• Analyzing data and identifying trends or deviations from standards

• Documenting test results and communicating findings to relevant stakeholders

• Troubleshooting issues and recommending corrective actions

• Ensuring compliance with regulatory requirements and quality standards

Alkanes, alkenes, and alkynes are hydrocarbons with different types of carbon-carbon bonds.

• Alkanes have single bonds between carbon atoms and are saturated hydrocarbons.

• Alkenes have at least one double bond between carbon atoms and are unsaturated hydrocarbons.

• Alkynes have at least one triple bond between carbon atoms and are also unsaturated hydrocarbons.

• The general formula for alkanes is CnH2n+2, for alkenes it is CnH2n, and for alkynes it is CnH2n-2.

• Examples of alkanes inc...read more

PH is a measure of acidity or alkalinity of a solution on a scale of 0 to 14.

• PH stands for 'potential of hydrogen'.

• It measures the concentration of hydrogen ions in a solution.

• A PH of 7 is considered neutral, below 7 is acidic, and above 7 is alkaline.

• Examples: Lemon juice has a PH of around 2, water has a PH of 7, and baking soda has a PH of around 9.

There are various types of cleaning methods used in manufacturing, including dry cleaning, wet cleaning, and solvent cleaning.

• Dry cleaning involves using a dry substance, such as compressed air or vacuuming, to remove dirt and debris.

• Wet cleaning involves using water or a cleaning solution to remove dirt and debris.

• Solvent cleaning involves using a solvent, such as alcohol or acetone, to dissolve and remove dirt and debris.

• Other types of cleaning methods include abrasive clea...read more

I have faced a total of 12 audits in my career as a QA Manager.

• I have faced audits from both internal and external auditors.

• I have experience in preparing for audits and ensuring compliance with regulations.

• Some of the audits I have faced include ISO 9001, FDA, and customer audits.

• I have also conducted audits of suppliers and vendors to ensure quality standards are met.

Acetone formula is C3H6O and toluene formula is C7H8.

• Acetone is a colorless liquid used as a solvent and in nail polish remover.

• Toluene is a colorless liquid used as a solvent and in the production of benzene and other chemicals.

Faraday's laws are two laws of electromagnetism that describe how a magnetic field is produced by an electric current and how an electric current is induced by a changing magnetic field.

• Faraday's First Law states that a change in magnetic field induces an electromotive force (EMF) in a closed circuit.

• Faraday's Second Law states that the magnitude of the induced EMF is directly proportional to the rate of change of magnetic flux through the circuit.

• These laws are fundamental i...read more

A solvent dispensing system is a device used to accurately dispense solvents for various applications.

• Solvent dispensing systems are commonly used in laboratories for tasks such as sample preparation and chromatography.

• They can be manual or automated, with automated systems offering greater precision and reproducibility.

• Some systems use positive displacement pumps to ensure accurate dispensing, while others use gravity or pressure-based systems.

• Solvent dispensing systems can ...read more

Water boils at 100 degrees Celsius or 212 degrees Fahrenheit.

• Water boils at 100 degrees Celsius or 212 degrees Fahrenheit at sea level.

• Boiling point of water can vary with altitude - it decreases as altitude increases.

• Adding salt or other substances to water can raise its boiling point.

• Boiling point can also be affected by pressure changes.

Normality refers to the state of being typical or conforming to a standard or norm.

• Normality can vary depending on the context, such as social norms, statistical norms, or medical norms.

• In statistics, normality refers to a bell-shaped curve distribution, known as a normal distribution.

• Normality can also refer to mental or physical health, where deviations from the norm may indicate a problem.

• Examples of normality include following societal norms, having a normal body temperat...read more

Blenders are kitchen appliances used to mix, puree, or emulsify food and other substances.

• Blenders have a motorized base with a container to hold the ingredients.

• They typically have sharp blades at the bottom of the container to blend the ingredients.

• Blenders can be used to make smoothies, soups, sauces, and other liquid-based recipes.

HPLC principle involves separating compounds in a mixture based on their interaction with a stationary phase and a mobile phase.

• HPLC stands for High Performance Liquid Chromatography.

• It works on the principle of separating compounds based on their affinity for the stationary phase (column) and the mobile phase (solvent).

• Compounds with higher affinity for the stationary phase will move slower through the column, leading to separation.

• The separated compounds are detected and qu...read more