Question

d) Why do we zero the instrument with the “blank” tube each time we change the wavelength?

e) If the Absorbance of one of your unknown solutions was almost twice as great as the absorbance of the most concentrated standard solution, what could you do to still accurately determine its concentration?

f) Consumption of methanol leads to blindness and even death. Why do you think methanol consumption is more poisonous than ethanol consumption? (Hint: what is the chemical difference between methanol and ethanol).?

Answer 1

d) THE blank tube is used as reference , ideally the blank should contain everything present in the solution except the substance we want to analyse ,

f) The consumption of methanol leads blindness and death as the methanol when ingested , it gets oxidised to formaldehyde(which causes blindness ) and the methanoic acid during the metabolic processes in the body , hence it causes blindness and can even lead to death . whereas ethanol doesnot form the harmful formaldehyde which can cause blindness , so methanol is toxic to heath whereas ethanol is normally present in beers , wine n rum.