Quiz 3 Flashcards
- Apparent changes in the pH solution when it is continuously used for 30 days without storage at 4 deg C.
A. microbial growth
B. unstable pH
C. high in nitrogenous substance
D. all of the above
A. microbial growth
- In redox titration, what chemical substance is added to the iodometry and iodometry analysis?
A. starch
B. phenolphthalein
C. glucose
D. argentum
A. starch
- The extent of radiation absorbed by the absorbing species is a function of the path length and the constant concentration of the absorbing species.
A. Beer-Lambert’s Law
B. Beer’s Law
C. Lambert’s Law
D. none of the above
A. Beer-Lambert’s Law
- Name the chloride of metal which dissolves in excess of ammonium hydroxide?
A. lead (II) chloride
B. copper (II) chloride
C. silver chloride
D. sodium chloride
C. silver chloride
- Which of the following acids can be used to acidify silver nitrate solution for the test of halides?
A. hydrochloric acid
B. dilute nitric acid
C. sulphuric acid
D. carbonic acid
B. dilute nitric acid
- After shaking the separating funnel, we should invert it and open the tap. Which of the following statements is the purpose for the above procedure?
A. to extract the desired substances more efficiently
B. to mix the two solvent layers by air
C. to get rid of the impurities
D. to release the pressure
D. to release the pressure
- Factors to be considered during preparation of the sample solution in gravimetric analysis?
A. pH
B. temperature
C. volume of solution
D. all of the above
D. all of the above
- Which of the following is known as calomel?
A. silver chloride
B. mercury chloride
C. potassium chloride
D. mercury sulphate
B. mercury chloride
- The chemical specie that is being measured is
A. analyte
B. a matrix
C. a compound
D. a component
A. analyte
- The liquid, solid or mixed material in which the analyte must be determined is
A. analyte
B. a matrix
C. a compound
D. a component
B. a matrix
- Which describes gravimetric analysis?
A. precipitate and weigh products
B. very precise
C. very limited
D. all of the above
D. all of the above
- If repeated measurements of the same thing are all very close to one another, then the measurement is
A. precise
B. accurate
C. estimated
D. all of the above
A. precise
- Random error is a measure of
A. precision
B. accuracy
C. true value
D. all of the above
A. precision
- Difference between the mean of a population of measurements and the true value.
A. systematic errors
B. random error
C. gross error
D. all of the above
A. systematic errors
- An analysis of the wavelength dependence on the absorbance or emission of light is called
A. spectroscopy
B. potentiometry
C. gravimetry
D. electrochemical analysis
A. spectroscopy
- Organic solvent that may be used to remove grease films.
formaline
benzene
toluene
chloroform
benzene
- Interaction of solute molecules (or atoms or ions) with the surface of the stationary phase in chromatography is
A. adsorption
B. absorption
C. desorption
D. all of the above
A. adsorption
- Which of the following is a chemical drying agent or desiccants?
A. anhydrous calcium chloride or calcium sulfate
B. magnesium perchlorate
C. phosphorous pentoxide
D. all of the above
D. all of the above
- Which of the following affects pipetting accuracy?
A. temperature and pressure
B. volume and pH
C. humidity and volume of sample
D. none of the above
A. temperature and pressure
- Most accurate pipets with well defined tolerance limits is
A. automatic pipets
B. class A
C. class B
D. serological pipets
B. class A