The height of three peaks; A, B, and C obtained in a gas chromatogram are 25.1 mm, 14.5 mm and 37.1 mm. The width of the peaks, at half height, are 4.6 mm, 4.4 mm and 5.9 mm, respectively. Calculate the percentage composition of A in the sample.

Percentage Compositon Of A in the sample= 28.99%

Explanation:

First we calculate the Peak area.

Because each peak is consdered like a triangle in a Chromatogram, The Area of the peak is calculated as  = height x half height of the width

Area of Pea A= 25.1 mm X 4.6mm=115.46mm2

Area of Peak B= 14.5mm x 4.4mm=63.8mm2

Area of PeaK C=  37.1mm x5.9mm =218.89mm2

Total Peak Area=  398.15mm2

Percentage Area of Peak A =  Area of Peak A/Total Peak Area x 100

= 115.46 / 398.15  x 100

=0.2899 x 100

=28.99%

Percentage Compositon Of A = 28.99%

in scientific notation, the value of the  speed of light in a vacuum

  will be written as 2.995 * 10^8. when this value is represented in the form of

  a * 10^b, then, a = 2.995 and b = 8.

the value of the speed of light in a vacuum given above can also be rounded up to approximately 300000000. in this case, the scientific notation will be written as 3 *10^8.