Question

An element X has the following isotopic composition 200x = 90 %, 199X = 8 % and 20X = 2 %. The weighted average atomic mass of the element X is closest to​

Answer 1

Answer:

Correct option is

B

200amu

Average atomic mass =

100

A

1

×X

1

+A

2

×X

2

+A

3

×X

3

Where,

A= Isotopic mass

X= Percentage of occurrence

Average atomic mass =

100

200×90+199×8+202×2