C215 EXAM REVIEW -QUESTIONS WITH COMPLETE ANSWERS

C215 EXAM REVIEW -QUESTIONS WITH COMPLETE ANSWERS which of the following orbitals of H has the highest energy 2p 4s 1s 3d - Answers- 4s a 100-mL sample of Pb initially has a concentration of 12.3 ppm, if this sample was diluted to 400 mL, what is the new concentration in ppm - Answers- 3.1 which of the following is directly proportional to the concentration of a solution sample (a)intensity of light passing through (b)extinct coefficient (c)transmittance of light (d)absorbance of light - Answers- (d)absorbance of light when measuring the transmittance of digested cereal sample, what is used as blank - Answers- cereal sample without complexing agents when intensity of light changes due to sample absorption, which of the following change accordingly (a)frenqency (b)energy of each photon (c)wavelength (d)transmittance - Answers- (d)transmittance if a Fe stock solution has a concentration of 1.6 mg/mL, what is the concentration when 2 mL of this stock solution is diluted to 50. mL - Answers- 0.064 what is the absorbance if the % transmittance is 43% - Answers- 0.37 (Absorbance=log(1oo/transmittance) the Total Cereal has a Fe concentration of 0.6 g Fe per g of cereal, however, it is very common for students to get less than 0.6, which of the following can be contributors to this lower experimental result than the manufacturer listed value (a)the Fe was oxidized from 2+ ion to 3+ ion (b)other materials from Cereal sample absorbs too much light (c)under-digestion of cereal sample (d)some Fe was lost during a few transfers between glassware