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.
A simple circuit consists of a battery to provide power, wires to carry the electrical power, and
load that uses the electrical power for example a light globe
good luck
Answer:
2.08 moles (3 s.f.)
Explanation:
number of moles
= number of atoms ÷ Avogadro's constant
Avogadro's constant= 6.022 ×10²³
Thus, number of moles
= 1.25×10²⁴ ÷ (6.022 ×10²³)
= 2.08 moles (3 s.f.)
On June 21, as seen from the North pole ...
-- the sun has been up, and it's been light outside,
for the past three months ... ever since March 21 .
-- The sun won't set, and it won't be dark outside,
for another three months ... until September 21.
-- Here at the North pole, it stays daylight for six months straight.
Today, on June 21, we're exactly halfway through the period of
continuous daylight.
Hello,
Here is your answer:
The proper answer to this question is option C "stigma".
Here is how:
The stigma is responsible for producing pollen in a plant.
Your answer is C.
If you need anymore help feel free to ask me!
Hope this helps!
