SATHEE: Some Basic Concepts of Chemistry

Some Basic Concepts of Chemistry - Result Question 15

####15. An element, $X$ has the following isotopic composition :

[2007]

$^{200} X : 90$

The weighted average atomic mass of the naturally occuring element $X$ is closest to

(a) $201 a m u$

(b) $202 a m u$

(d) $200 a m u$

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Solution:

(d) Average isotopic mass of

$\begin{aligned} X = \frac{200 \times 90 + 199 \times 8 + 202 \times 2}{90 + 8 + 2} \\ = \frac{18000 + 1592 + 404}{100} \\ = \frac{19996}{100} = 199.96 ≃ 200 a m u \end{aligned}$

Average atomic mass

$= ($ Mass of isotope $A \times$ natural abundance $) +$ (Mass of isotope B $\times$ natural abundance) + (% Natural abundance of $A +$ natural abundance of B) + …….

Some Basic Concepts of Chemistry - Result Question 15

Solution:

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Some Basic Concepts of Chemistry - Result Question 15

Solution:

Engineering Preparation

Medical Preparation

NCERT Books & Solutions

Important Resources

Other Resources

Syllabus

Test Platform

Sample Mock Test

Mentorship

NCERT Exercise Video Solution

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