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sertanlavr [38]
3 years ago
8

The level of a liquid (i.e. distilled water) in laboratory glassware is determined by sight. The level corresponds to a specific

volume. The volume is established by identifying the meniscus of the liquid relative to a calibration mark or series of calibration marks on the glassware (i.e. volumetric flask vs. buret). Which of the following statements is NOT correct when reading the meniscus?
a. the edge of the meniscus should be used to determine volume relative to the mark or marks
b. the meniscus should be read at eye level
c. when the meniscus is between marks, estimate the reading to the nearest tenth of a division (ie, estimate to 0.01 mL if buret has 0.1 ml divisions)
d. the center of the meniscus should be used to determine volume relative to the mark or marks
Chemistry
1 answer:
Sati [7]3 years ago
7 0

Answer:

c. when the meniscus is between marks, estimate the reading to the nearest tenth of a division (ie, estimate to 0.01 mL if buret has 0.1 ml divisions)

Explanation:

When we put a liquid in a pipette, we can see that the surface of that liquid will have a curve. This curve is called the meniscus and it has the correct volume that an aqueous solution has. However, for this, it is necessary that the meniscus is observed at eye level and that its edges and center are clearly visible.

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A 52.0-mL volume of 0.35 M CH3COOH (Ka=1.8×10−5) is titrated with 0.40 M NaOH. Calculate the pH after the addition of 23.0 mL of
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<span>31.0ml of 0.40M NaOH : .031 L(0.40M) = .0124 mol of NaOH. 
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Explanation:

According to question,  protein contains one tyrosine residue and say x number of tryptophans.

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Molar absorptivity of a protein solution : \epsilon

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