EY Global Delivery Services ( EY GDS) Interview Questions and Answers

To increase intensity in TLC plate, use a more concentrated sample or increase the amount of sample spotted.

• Use a more concentrated sample

• Increase the amount of sample spotted

• Use a more sensitive detection method

• Increase the development time

• Use a different solvent system

ODS and BDS columns are both used in chromatography but differ in their stationary phase.

• ODS (Octadecylsilane) columns have a hydrophobic stationary phase and are used for non-polar compounds.

• BDS (Butylsilane) columns have a more polar stationary phase and are used for polar compounds.

• ODS columns are more commonly used than BDS columns.

• Both columns have different selectivity and retention characteristics.

C8 and C18 columns differ in their hydrophobicity and selectivity.

• C8 columns have shorter carbon chains than C18 columns.

• C8 columns are less hydrophobic than C18 columns.

• C8 columns are more selective for less hydrophobic compounds.

• C18 columns are more selective for more hydrophobic compounds.

• C8 columns are often used for separating polar and nonpolar compounds.

• C18 columns are often used for separating nonpolar compounds.

• C8 columns have a lower retention time than C18 columns....read more

Retardation factor is the ratio of the distance traveled by a solute to the distance traveled by the solvent in a chromatography experiment.

• Retardation factor is a dimensionless quantity.

• It is used to identify and separate different components of a mixture in chromatography.

• It is calculated by dividing the distance traveled by the solute by the distance traveled by the solvent.

• Retardation factor values range from 0 to 1.

• A higher retardation factor indicates that the solute is...read more

Lambert Beer Law states that the absorbance of a solution is directly proportional to the concentration of the absorbing species.

• The law is used to determine the concentration of a substance in a solution by measuring its absorbance.

• It assumes that the absorbing species is uniformly distributed throughout the solution.

• The law is expressed as A = εcl, where A is the absorbance, ε is the molar absorptivity, c is the concentration, and l is the path length.

• The law is widely used...read more