Let’s say you have 3 UV active spots in the crude material and co-spot TLC plate. One has the same Rf value as the starting mate
rial and the other 2 are very different. What could these 2 nonstarting material spots be? Use structures and words. Hint: think about the nucleophilic addition of the hydride.
2 answers:
Answer:
Answer: (1R,2S) / (1S, 2R) , (1R,2R) / (1S, 2S)
Explanation:
Sodium borohydride reduction of benzoin will give four possible stereo isomers out of which are (1R,2S) - (1S, 2R) isomers and (1R,2R) - (1S, 2S) isomers which are known as enantiomers.
In general enantiomers show single spot in the TLC as they do not show any difference in Rf value (i.e) (1R,2S) - (1S, 2R) isomers show only one spot although they are two compounds and also (1R,2R) - (1S, 2S) isomers also show one spot. That is the reason why you are observing two spots in the TLC ( of reaction mixture) other than starting materilal.
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Answer: 67.2 moles
Explanation:
According to the given balanced equation, 2 moles of acetylene combine with 5 moles of oxygen
to produce 4 moles of carbon dioxide
.
Thus if 2 moles of acetylene combine with = 5 moles of oxygen
35 moles of acetylene combine with=
moles of oxygen
But as only 84 moles of oxygen are available, acetylene is not a limiting reagent.
5 moles of oxygen reacts with = 2 moles of acetylene
84 moles of oxygen reacts with=
moles of acetylene
Thus Oxygen is the limiting reagent as it limits the formation of products. Acetylene is excess reagent as it is present in excess.
2 moles of acetylene produce= 4 moles of carbon dioxide
.
33.6 moles of acetylene produce=
moles of of carbon dioxide
.
The moles can be defined as the mass of the substance with respect to molar mass. The moles of potassium nitrate is 1 mol.
<h3>How to calculate moles of a substance?</h3>The moles of a compound can be calculated from:
The molarity can be defined as the moles of solute in a liter of solution.
The molarity can be expressed as:
The molarity of potassium nitrate solution is 2 M, and the volume is 500 mL.
The moles of potassium nitrate is given as:
The moles of potassium nitrate in 2 M, 500 mL solution are 1 mol.
Learn more about moles, here: