Answer:
<h3>Step 1: </h3>
To relate the volume and molarity of a solution at two different concentrations, the expression used is :
M₁V₁ = M₂V₂
<h3>
step 2:</h3>
(2M) V₁ = (0.15M)(250ML)
V₁ = 18.75
step 3:
<h2>Pls, branliest! :)</h2>
Answer: W + BgCz2 arrow WCz + Bg
2 W + BgCz2 arrow 2 WCz + Bg
Explanation:
Cz has 2 so you balcne the other side of WCz.
Since you Balcanes the Cz you changed the W and you Balcanes the other W on the left side.
Answer: Natural selection.
Explanation:
The natural selection is the process by which the organism that best suits the characters will survive and the organism which cannot adapt the changes will die.
The predators feed on their prey and the organism which hides easily in the environment due to its color is safe and the animals that cannot camouflage will die.
This is natural selection that more favored character is carried out over generations and other that cannot survive die.
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.