Question

A robot spacecraft returned samples from the planetesimal 98765 ALEKS, located in the outer Solar System. Mass-spectroscopic analysis produced the following data on the isotopes of molybdenum in these samples: isotope mass relative (amu) abundance 94 Mo 93.91 41.% 92 Mo 91.91 59.% Use these measurements to complete the entry for molybdenum in the Periodic Table that would be used on 98765 ALEKS. Round your entry for the atomic mass to 2 significant digits. Caution: your correct answer will have the same format but not necessarily the same numbers as the entry for molybdenum in the Periodic Table we use here on Earth. Txo ?

Answer 1

Given

Isotope – ⁹⁴Mo

Mass is 93.91 amu

Relative abundance – 41%

Isotope – ⁹²Mo

Mass is 91.91 amu

Relative abundance – 59%

Now

Atomic mass = ∑ (Isotope Mass* Relative abundance)/100

= (93.91 amu*41 + 91.91 amu*59)/100

= 92.73 amu

= 93 amu

Mo Atomic number is 42

so

symbol is

₄₂⁹³Mo