In this case, considering that the compound is 48% oxygen, we infer it is 52% chromium, therefore, by using their atomic masses we compute the moles by assuming those percentages as masses:

$n_{Cr}=52g*\frac{1mol}{52g}=1mol\\ \\n_O=48g*\frac{1mol}{16g}=3mol$

Next, by dividing by the smallest moles, we find the subscripts in the empirical formula:

$Cr=\frac{1}{1} =1\\\\O=\frac{3}{1} =3$

Which are also expressed in the smallest whole numbers, therefore the empirical formula is:

$CrO_3$

Which corresponds to the chromic oxide or chromium (IV) oxide.

Regards.

6 0

3 years ago

WHY ACETIC ACID IS STRONGER IN STRENGHT THAN CHLOROACETIC ACID ...?

aleksandr82 [10.1K]

For this question, I think it is the other way around. It is true that chloroacetic acid is stronger in strength than acetic acid. Acid strength is measured as the equilibrium constant of the reaction <span>HA -----> H+ + A-

</span><span> In acetic acid, the anion produced by dissociation is CH3-COO-; in chloroacetic acid it is CH2Cl-COO-. Comparing the two, in the first one the negative charge is taken up mostly by the two oxygen atoms. In the second there is also an electronegative chlorine atom nearby to draw more charge towards itself. Therefore, the charge is less concentrated in the chloroacetate ion than it is in the acetate ion, and, accordingly, chloroacetic acid is stronger than acetic acid. </span>

6 0

3 years ago