Answers

2014-10-01T19:44:53+05:30

This Is a Certified Answer

×
Certified answers contain reliable, trustworthy information vouched for by a hand-picked team of experts. Brainly has millions of high quality answers, all of them carefully moderated by our most trusted community members, but certified answers are the finest of the finest.
When isotopes are present, atomic mass is taken as their weighted average.
Let percentage of 17c|35 chlorine = x%
      percentage of 17c|37 chlorine = (100-x)% (as only 2 isotopes are there)

Atomic weight = [(35 × x) + ( 37× (100-x))] / 100
⇒35.5 = [35x + 3700 -37 x ] / 100
⇒3550 = -2x + 3700
⇒ 3550-3700 = -2x
⇒ 2x = 150
⇒ x = 75
100 - x = 25

So percentage of 17c|35 chlorine = 75%
      percentage of 17c|37 chlorine = 25%

Answer is (2).
0
2014-10-05T09:53:19+05:30
Let %  abundance of 17cl35 be x%
then % abundance  of  17cl37 =(100-x)% (as sum of their % abundance will be 100)
then,
35.5=35*x+37*(100-x)/100
35.5*100=35x+3700-37x
3550=3700-2x
2x=3700-3550
2x=150
x=75
therefore % abundance of 17cl35=75%
and % abundance of 17cl37=(100-75)%=25%

0