Respuesta :
If 28.00 g of plasma needs to be titrated with 35.46 mL of 0.05961 M Cr₂O²₇, then the mass percent of alcohol in the blood is 0.1743%.
We know that 35.46 mL of a 0.05961M (mol/L) Cr₂O²₇ have been used.
35.46mL always change to L = 34.46 X 1L/1000mL = 0.03546L
0.05961mol/L of Cr₂O²₇ X 0.03546L = 0.002114 mol of Cr₂O²₇
Now that we know how many moles of Cr₂O²₇ were utilized, the question of C₂H₅OH(aq) is raised (aq).
So we need to use the balanced equation. 1 mol of C₂H₅OH(aq) is equal to how many Cr₂O²₇?
So now we get:
0.002114 mol Cr₂O²₇ X [tex]\frac{1 mol C_{2} H_{5}OH }{2 mol of Cr_{2}O_{7}^{2} }[/tex] = 0.001057 mol C₂H₅OH(aq)
Now how do we get from moles to grams?
We make use of the compound's molar mass. Thus, we obtain 46 grams for C₂H₅OH(aq).
0.001057mol C₂H₅OH(aq) X [tex]\frac{46 g C_{2} H_{5} OH }{1 mol C_{2} H_{5} OH }[/tex]) = 0.04862 g C₂H₅OH(aq)
Now to get the percentage of mass we need to use the formula (mass it took to titrate / mass of plasma)*100
([tex]\frac{0.04862 g C_{2} H_{5} OH }{27.90g}[/tex] ) X100% = 0.1743%
What steps are involved in titration?
Titration is a method of chemical analysis in which the amount of a sample's constituents is determined by adding a precise amount of a different substance—one that the desired constituent reacts with in a specific, known proportion—to the sample being tested.
Learn more about titration: https://brainly.com/question/16254547
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