Anew element was recently discovered and found to have an atomic weight of 342.38 amu. this element has two isotopes, the lighter of which has a mass of 340.91 amu and an abundance of 68.322%. what is the mass of the heavier isotope?

Atomic weight of new element is 342.38 amu. The mass of lighter isotope is 340.91 amu and abundance 68.322 %.

Since, the total abundance is 100% , the abundance of heavier isotope will be (100-68.322) %=31.678%

The formula for atomic weight or average atomic weight of element is as follows:

Average atomic weight= Mass of lighter isotope×% abundance of lighter isotope+Mass of heavier isotope×% abundance of heavier isotope.

Putting the values,

Average atomic weight= 340.91×0.68322+Mass of heavier isotope×0.31678

342.38 amu=232.91+Mass of heavier isotope×0.31678

On rearranging,

Thus, mass of heavier isotope will be 345.55 amu.

here is table 2-2:

country

percent of eligible voters that voted

rank

united states

44.9%

138

canada

60.1%

107

costa rica

84.6%

14

hungary

66.9%

82

japan

57.0%

118

egypt

27.7%

159

south africa

85.5%

10

ans is no, the data set cannot be plotted as a single circle graph