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a. The mass spectrum of boron shows peaks at m/z10 and 11 . The intensity of these peaks are 19.8% and 80.2% respectively. Sketch the mass spectra with labelled axes. b. Calculate the relative atomic mass of boron using the data given in the question.

User Sallyann
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Final answer:

The mass spectrum of boron shows peaks at m/z10 and 11, with intensities of 19.8% and 80.2% respectively. The relative atomic mass of boron is calculated as 10.8 amu.

Step-by-step explanation:

The mass spectrum of boron shows peaks at m/z10 and 11. The intensity of these peaks are 19.8% and 80.2% respectively. To sketch the mass spectra, you would have a graph with mass-to-charge ratio (m/z) on the x-axis and intensity on the y-axis. The peak at m/z10 would have a height of 19.8% and the peak at m/z11 would have a height of 80.2%. The graph would include labels for the axes.

To calculate the relative atomic mass of boron using the given data, you would multiply the mass of each isotope by its relative abundance (given as a percentage), then add the products together. In this case, the calculation would be (0.20) (10) + (0.80) (11) = 10.8 amu. Thus, the atomic mass of boron is 10.8 amu.

User Sparlarva
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a. the mass spectra with labelled axes is attached

b. relative atomic mass of boron is 10.8 u.

The mass spectrum of boron shows two peaks, one at m/z 10 and the other at m/z 11. The intensity of the peak at m/z 10 is 19.8%, while the intensity of the peak at m/z 11 is 80.2%. This is because boron has two naturally occurring isotopes, 10B and 11B. The relative abundance of these isotopes is reflected in the intensities of the peaks in the mass spectrum.

Relative atomic mass = (mass of isotope 1 * abundance of isotope 1) + (mass of isotope 2 * abundance of isotope 2)

e mass of 10B = 10.0129 u

the mass of 11B = 11.0093 u.

The abundance of 10B = 19.8%, and the abundance of 11B = 80.2%.

Relative atomic mass = (10.0129 u * 0.198) + (11.0093 u * 0.802)

= 10.8 u

In conclusion, the relative atomic mass of boron is 10.8 u.

a. The mass spectrum of boron shows peaks at m/z10 and 11 . The intensity of these-example-1
User OOPer
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