Which formula represents chromium(III) oxide?(1) CrO3 (3) Cr2O3 (2) Cr3O (4) Cr3O2
- Mayya Alocci
- May 22, 2023
- 1 min read
NY Regents Chemistry Exam Jan 2023
Which formula represents chromium(III) oxide? (1) CrO3
(2) Cr3O
(3) Cr2O3
(4) Cr3O2
Solution: Chromium oxide is an ionic compound because it is composed of a metal and a nonmetal. The charge of Cr is 3+ according to the roman numeral in the formula. The charge of O is -2 according to the Periodic Table. We cross multiply the numbers get the correct formula. Cr should get 2 from oxygen and O should get 3 from the chromium. We get Cr2O3, choice 3