What is the empirical formula of a barium salt that contains 17.14*g of the metal, and 8.86*g of chlorine?

1 Answer
Mar 26, 2017

You mean the "empirical formula"........... and here it is BaCl_2.

Explanation:

You mean the "empirical formula"...........

The "empirical formula" is the simplest whole number defining constituent atoms in a species. And it is calculated by taking percentage mass of each element, and dividing thru by atomic mass, and then modifying these percentages to give simple whole numbers.

And thus %Ba = (17.14*g)/(17.14*g+8.86*g)xx100%=65.9%

And thus %Cl = (8.86*g)/(17.14*g+8.86*g)xx100%=34.1%

You will note of course that the percentages sum to 100%. Why "of course?"

And then we assume 100*g of compound and divide thru by the atomic masses of each constituent:

"Moles of barium" = (65.9*g)/(137.3*g*mol^-1)=0.480*mol.

"Moles of chlorine" = (34.10*g)/(35.5*g*mol^-1)=0.960*mol.

If we divide thru by the smallest molar quantity, CLEARLY, we get an empirical formula of BaCl_2...........