Quiz on Practical Instrumental Analysis

What is the objective of Experiment 1?

• To analyze a two-component mixture by UV-Visible

• To measure the refractive index of distilled water and ethanol

• To determine the concentration of potassium dichromate

• To determine the absorption spectrum of potassium dichromate

What is the refractive index defined as?

• The measure of light absorption in a medium

• The ratio of the velocity of light in a substance to its velocity in vacuum

• The density of a liquid divided by its molar mass

• The angle of incidence divided by the angle of refraction

Which chemical is used in Experiment 3 to determine λmax?

• Sodium chloride

• Potassium dichromate

• Ethanol

• Methanol

What is the first step in the procedure for Experiment 1?

• Calibrate the refractometer

• Prepare distilled water in a beaker

• Clean the application area of refractometry

• Record the refractive index

What is the purpose of constructing a calibration curve in Experiment 2?

• To determine the percent composition of components in a solution

• To measure the absorption spectrum of ethanol

• To find the refractive index of distilled water

• To determine the molar mass of potassium dichromate

What is the molar refraction formula used for?

• To calculate the density of a liquid

• To determine the refractive index of a solution

• To calculate the atomic refraction of a compound

• To measure the bending of light in different media

In Experiment 2, what is the composition of methanol when ethanol is 80 ml?

• 50 ml

• 20 ml

• 30 ml

• 40 ml

What is the significance of λmax in qualitative analysis?

• It indicates the density of a solution

• It is the wavelength at which a species absorbs maximum light

• It determines the refractive index of a solution

• It measures the concentration of a solution

What is the angle of incidence in the problem statement of Experiment 1?

• 60º

• 30º

• 48º

• 32º

What is the first step in preparing the potassium dichromate solution?

• Record the absorbance

• Set the spectrophotometer to 325 nm

• Add 100 ml of distilled water

• Weigh out approximately 0.93g of potassium dichromate