Question

3. 00 How would you define the terms atomic mass and
molecular mass ?
() Nitrogen occurs in nature in the form of two isotopes with
atomic masses 14 and 15 respectively. If the average
atomic mass of nitrogen is 14.0067, what is the percent
abundance of the two isotopes?​

Answer 1

Answer:

Mass is a property of a physical object that quantifives the amount of matter it contains

Answer 2

Answer:-

Let

• %abundance of N-14 isotope=x
• %abundance of N-15 isotope=100-x

The average atomic mass=14.0067

$\\ \sf\longmapsto \dfrac{14\times x+(100-x)15}{100}=14.0067$

$\\ \sf\longmapsto \dfrac{14x+(100-x)15}{100}=14.0067$

$\\ \sf\longmapsto \dfrac{14x+1500-15x}{100}=14.0067$

$\\ \sf\longmapsto -x+1500=1400.67$

$\\ \sf\longmapsto -x=1400.67-1500$

$\\ \sf\longmapsto -x=-99.33$

$\\ \sf\longmapsto x=99.33$

$\\ \sf\longmapsto 100-x=100-99.33=0.67$

Hence

$\\ \underline{\boxed{\bf{\therefore \%\:abundance\:of\:N-14 \:isotope\:is \:99.33\%}}}$

$\\ \underline{\boxed{\bf{\therefore \%aboundance\:of\:N-15\:isotope\:is\:0.67\%.}}}$