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.
The statement which is true is
Fluorine is more reactive than nitrogen because fluorine needs only one electron to fill its outermost shell.
<u><em>Explanation</em></u>
Fluorine has electron configuration of 1S²2S²2P⁵ while nitrogen has 1S²2S²2P³ electron configuration.
The 2P sub shell for nitrogen is half filled therefore it is sable than fluorine.
since p orbital can hold a maximum of 6 electrons ,Fluorine requires 1 electron to completely fill it's 2P sub shell which make it more reactive than nitrogen.
Because its only representing the most stable isotope of that element but its considered the atomic mass and not average atomic mass
Answer:
0.0344 moles and 1.93g.
Explanation:
Molarity is defined as the ratio between moles of a solute (In this case, KOH), and the volume. With molarity and volume we can solve the moles of solute. With moles of solute we can find mass of the solute as follows:
<em>Moles KOH:</em>
15.2mL = 0.0152L * (2.26mol / L) = 0.0344moles
<em>Mass KOH:</em>
0.0344 moles * (56.11g/mol) = 1.93g of KOH
