Bissoy.com
Doctors Medicines MCQs Q&A

The molar extinction coefficient of B (MW = 180) is 4 x 103 L mol-1 cm-1. One-liter solution of C which contains 0.1358 g pharmaceutical preparation of B, shows an absorbance of 0.411 in a 1 cm quartz cell. What is the percentage (w/w) of B in the pharmaceutical preparation?

The molar extinction coefficient of B (MW = 180) is 4 x 103 L mol-1 cm-1. One-liter solution of C which contains 0.1358 g pharmaceutical preparation of B, shows an absorbance of 0.411 in a 1 cm quartz cell. What is the percentage (w/w) of B in the pharmaceutical preparation? Correct Answer 13.60

n:

Related Questions

The ultraviolet spectrum of benzonitrile shows a primary absorption band at 224 nm. If a solution of benzonitrile in water, with a concentration of 1x 10-4 molar, is examined at a wavelength of 224 nm, the absorbance is determined to be 1.30. The cell length is 1 cm. What is the molar absorptivity of this absorption band?
A quartz crystal of thickness 0.001m is vibrating at resonance. Calculate the fundamental frequency. Density of quartz = 2.650×103 kg/m3 and Young’s modulus for quartz = 7.9×1010 N/m2.
A 60% spirit solution is mixed with r% spirit solution in the ratio 1 : 3 such that a s% spirit solution is obtained. When a (s/3)% spirit solution is mixed with 55% spirit solution in equal ratio, an (r/2)% spirit solution is obtained. Which of the following can be determined? (A) Value of ‘r’ (B) Value of ‘s’ (C) Volume of the 60% spirit solution mixed initially (D) If 9 liters of r% spirit solution was mixed initially, what was the volume of the s% spirit solution thus obtained?
The given table shows the number of employees appointed by different organizations in the given years. Year Organizations P Q R S T U 2007 92 102 84 100 95 98 2008 104 107 94 99 96 105 2009 96 119 93 102 98 103 2010 101 100 86 88 97 107 2011 85 117 84 103 102 99 2012 88 97 89 100 103 102   In the year 2008, the number of employees appointed by the organization R is how much percentage more from the previous year? (Around the nearest integer)
Suppose you have four test tubes labelled as 'A', 'B', 'C' and 'D'. 'A' contains plain water, 'B' contains solution of an alkali, 'C' contains solution of an acid, and 'D' contains solution of sodium chloride. Which one of these solution will turn phenophthalein solution pink?
The ultraviolet spectrum of benzonitrile shows a secondary absorption band at 271 nm. If a solution of benzonitrile in water, with a concentration of 1×10-4 molar solution is examined at 271 nm, what will be the absorbance reading (ℇ = 1000) and what will be the intensity ratio, IO/I, respectively?
A chemical solution appears green when the salt concentration is 8 grams per litre (gpl) and red when it is 10 gpl. Pure water was added to the solution of 1 litre of 15 gpl solution till it turned green. Then 125 ml of the green solution is taken out and x grams of salt is added to the green solution to make it red. Another 500 ml of the final solution was taken out and y litres of green solution is added to get a resultant solution of concentration 9.6 gpl.  Assume adding salt doesn’t change its volume and find the ratio of x and y. 
Only if the calculated molar mass is higher than the actual molar mass of the solute, the calculated molar mass is considered to be abnormal molar mass.
Consider the following statements about "Mass Extinction" 1. Mass extinction refers to when the Earth loses more than three-quarters of its species in a geologically short period of time. 2. So far, during the entire history of the Earth, there have been four mass extinctions, and we are experiencing the sixth mass extinction. Which of the above statements is/are incorrect?
Choose the sentences which can be S2 and S3. S1: Extinction of a particular animal or plant species occurs when there are no more individuals of that species alive anywhere in the world - the species has died out. S2: S3: S4: Today human intervention is causing rapid extinction of animals. P. For example, a mass extinction caused the death of many different types of animals and plants, including the dinosaurs. Q. Sometimes extinctions happen at a much faster rate than usual. R. This is a natural part of evolution.