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 problem the answer u are looking for a
4 moles of sugar.
Explanation:
A mole is defined as the amount of a substance contained in Avogadro's number of particles 6.02 x 10²³.
1 mole of substance = 6.02 x 10²³. molecules
Given that;
the sample of sugar contains 1.505 x 10²³.molecules
The number of moles in this amount of sugar is 4 moles
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Number of moles brainly.com/question/13064292
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Answer:
Common combustion reactions break the bonds of hydrocarbon molecules,
Explanation:
the resulting water and carbon dioxide bonds always release more energy than was used to break the original hydrocarbon bonds. That's why burning materials mainly made up of hydrocarbons produces energy and is exothermic.
