1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

# Chlorine exists in two isotopic forms, Clâˆ’37 and Clâˆ’35 but its atomic mass is 35.5. This indicates the ratio of Clâˆ’37 and Clâˆ’35 is approximately:

A
1:2
No worries! Weâ€˜ve got your back. Try BYJUâ€˜S free classes today!
B
1:1
No worries! Weâ€˜ve got your back. Try BYJUâ€˜S free classes today!
C
1:3
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
3:1
No worries! Weâ€˜ve got your back. Try BYJUâ€˜S free classes today!
Open in App
Solution

## The correct option is C 1:3Let relative abundance of Cl-37 be A1% with mass M1=37 amu∴ The relative abundance of Cl-35 = A2% with mass, M2=35 amuwhere A1+A2=100Thus A2%=(100−A1)%Using average atomic mass, Mavg=M1A1+M2A2A1+A2Mavg=37×A1+35×(100−A1)A1+(100−A1)=2A1+3500100Given that: Mavg=35.5∴2A1+3500100=35.52A1=35.5×100−3500=50A1=502=25 and A2=100−A1=100−25 =75Thus the ratio of isotope abundance of Cl−37toCl−35 is A1:A2=25:75=1:3So, the correct option is C

Suggest Corrections
0
Join BYJU'S Learning Program
Related Videos
Isotopes and Isotones
CHEMISTRY
Watch in App
Explore more
Join BYJU'S Learning Program