Chemistry Help about chemical formulas......Please HELP?

Question

The insecticide DDT has the composition by mass as given: Carbon 47.5%, Hydrogen 2.54% and chlorine 47.5%. What is empirical formula for DDT?

Please help me for this question....PLEASE!! and also give explanation for your answer. Please help...

There is another question of mine in the PHYSICS category. I have got answers but not complete. Please if any Physics master knows it, then help me for that question as well. It's about equilibrium....

Answer 1

Sorry but your question is not right because 47.5 + 2.54 + 47.5 < 100

in any case divide the % of C by 12.011 , the % of H by 1.008 and the % of Cl by 35.453

So you find the ratio between C , H and Cl.

Divide by the smallest number to find the ratio

I have calculed the correct %

C = 47.5

H = 2.55

Cl = 50.0

47.5 / 12.011 =3.95 => C

2.55 / 1.008 = 2.53 => H

50.0 / 35.453 = 1.41 => Cl

3.95 / 1.41 = 2.80

2.53 / 1.41 = 1.79

1.41 / 1.41 = 1

we get

C ( 2.80) H ( 1.79) Cl ( 1)

to have whole numbers we multiply by 5

2.80 x 5 = 14 => C

1.79 x 5 = 9 => H

1 x 5 = 5 => Cl

the formula is C14H9Cl5