hello sir,

please explain the below two questions.

Asked by seeni2005 | 20th Jul, 2020, 08:18: PM

Expert Answer:

Dear student,
You can find out molecular formula by following these steps-
1.
straight C space space space space space space space space space space space space space space space space straight H space space space space space space space space space space space space space space space space space straight N
66.7 percent sign space space space space space 7.41 percent sign space space space space space space space space 25.90 percent sign
left parenthesis 1 right parenthesis Divide space by space atomic space masses
fraction numerator 66.76 over denominator 12 end fraction space space space space space space space space fraction numerator 7.41 over denominator 1 end fraction space space space space space space space space space fraction numerator 25.90 over denominator 14 end fraction

5.56 space space space space space space space space space space space 7.41 space space space space space space space space space space space space 1.85
left parenthesis 2 right parenthesis Dvide space by space least space number
fraction numerator 5.56 over denominator 1.85 end fraction space space space space space space space space fraction numerator 7.41 over denominator 1.85 end fraction space space space space space space space fraction numerator 1.85 over denominator 1.85 end fraction
3.00 space space space space space space 4.00 space space space space space space space space space space space 1

left parenthesis 3 right parenthesis space Empirical space Formula equals straight C subscript 3 straight H subscript 4 straight N
Empirical space formula space mass equals space 12 cross times 3 plus 4 plus 14 equals 54

left parenthesis 4 right parenthesis space straight n equals fraction numerator Molecular space mass over denominator Empirical space mass end fraction equals 108 over 54 equals 2

left parenthesis 5 right parenthesis space Moleular space Formula equals straight n cross times Empirical space Formula
space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space equals 2 cross times straight C subscript 3 straight H subscript 4 straight N
space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space space equals straight C subscript 6 straight H subscript 8 straight N subscript 2


2.

straight C space space space space space space space space space space straight H space space space space space space space space space space space space space space space straight N space space space space space space space space space space space space space space straight O
32 over 12 space space space space space fraction numerator 6.67 over denominator 1 end fraction space space space space space space fraction numerator 18.66 over denominator 14 end fraction space space space space space space fraction numerator 42.67 over denominator 16 end fraction
2.66 space space space space 6.67 space space space space space space space space 1.332 space space space space space space space 2.66
fraction numerator 2.66 over denominator 1.332 end fraction space space space fraction numerator 6.67 over denominator 1.332 end fraction space space space space fraction numerator 1.332 over denominator 1.332 end fraction space space space space fraction numerator 2.66 over denominator 1.332 end fraction
2 space space space space space space space space space space space space space space space 5 space space space space space space space space space space space 1 space space space space space space space space space space space space space 2
Empirical space Formula equals straight C subscript 2 straight H subscript 5 NO subscript 2
Empirical space formula space mass equals 12 cross times 2 plus 5 plus 14 plus 32 equals 75
straight n equals 75 over 75 equals 1
Molecular space mass equals 75 cross times 1 equals 75

Answered by Ravi | 21st Jul, 2020, 03:34: PM