Question

Naturally occurring Indium has two isotopes.

Answer 1

Answer:

Average Molar mass is 114.8u

Explanation:

» From the formula of average Relative Atomic Mass [ RAM ]

${ \rm{RAM = \sum \frac{(isotopic \: mass \times \%abundance)}{100} }}$

» We have two isotopes of Indium,

• Indium-113, mass » 112.9u, % » 4.28%
• Indium-115, mass » 114.9u, % » 95.72%

${ \tt{RAM = \frac{ \blue{(112.9 \times 4.28)} + { \green{(114.9 \times 95.72)}}}{100} }} \\ \\ { \tt{RAM = \frac{11481.44}{100} }} \\ \\ { \underline{ \underline{ \tt{ \: RAM = 114.8\: }}}}$