Answer:
he percentage composition of peak "a" in the sample is approximately 19.05%.
Step-by-step explanation:
To calculate the percentage composition of peak "a" in the sample, we need to determine the area under the peak for each of the three peaks (a, b, and c) and then calculate the percentage of the total area that corresponds to peak a.
The area under a peak is proportional to the number of molecules that contributed to the peak, so if we assume that the peaks are due to different compounds, we can use the areas to determine the relative amounts of each compound.
First, we need to calculate the area of each peak. The area of each peak can be calculated by multiplying the width at half height by the height of the peak, and then multiplying by a conversion factor to convert from mm to a suitable unit (e.g., cm):
Area of peak a = (2.3/10) x 27.7 = 6.37 cm^2
Area of peak b = (4.9/10) x 11.7 = 5.71 cm^2
Area of peak c = (5.7/10) x 37.5 = 21.38 cm^2
Next, we can calculate the total area under all three peaks:
Total area = Area of peak a + Area of peak b + Area of peak c
Total area = 6.37 + 5.71 + 21.38
Total area = 33.46 cm^2
Finally, we can calculate the percentage of the total area that corresponds to peak a:
Percentage of area due to peak a = (Area of peak a / Total area) x 100
Percentage of area due to peak a = (6.37 / 33.46) x 100
Percentage of area due to peak a = 19.05%
Therefore, the percentage composition of peak "a" in the sample is approximately 19.05%.