Remember the acronym "Oil Rig". Oxidation is loss, Reduction is gain of electrons. Calcium is losing electrons so it's an oxidation reaction.
The purpose of using distilled water in the cuvette of the spectrophotometer is to calibrate the instrument. It is generally considered that distilled water shows zero absorbance and 100 % transmittance. So, to zero out the absorbance of compounds other than the analyte being determined, distilled water is used as a blank.
If the unknown being determined is prepared using ethanol as the base solution, the blank used must be ethanol. This is because absorbance if any from the solvent, ethanol must be zeroed out as when the measurement of the actual unknown is being made, the absorbance of the solvent does not interfere.
Answer:
The correct answer is - may not be typical, and participant burden.
Explanation:
The 24-hour recall is nothing but a retrospective method of diet assessment. In this method, an individual is interviewed about his or her diet consumption during the last 24 hours.
The disadvantages or limitations of this method include the inability of a single day's intake to describe the typical diet, multiple recalls to intake, cost and administration time; participant burden, have to recall to reliably estimate usual intake.
Answer:
zince chloride will be formed and hydrogen gas will be librated.
Explanation:
When dilute HCl is added to zinc pieces, a rection will takes place as follows :
It means that zinc chloride will form when zinc reacts with dilute HCL. Also hydrogen gas will produced.
As zinc is more reactive than hydrogen, it displaces hydrogen from its solution and forms zinc chloride. The form product is white in color and H₂ is an odorless gas.
Hence, zince chloride will be formed and hydrogen gas will be librated.
