Formula Writing Practice – Level 2 (Intermediate)
Section 1: Below are several covalent compounds. Please write the formulas of the compounds.
Example: Phosphorous hexachloride = PCl6
1. Phosphorus trichloride:___________
5. Boron trifluoride:_____________
2. Dinitrogen pentoxide:_____________
6. Carbon tetrachloride:_____________
3. Sulfur tetrabromide:_____________
7. Carbon dioxide:_____________
4. Nitrogen monoxide:_____________
8. Carbon monoxide:_____________
Section 2: Write the oxidation states for the following main group elements and polyatomic ions:
1. Cl ____
5. NO3____
9. NH4____
13. C2H3O2___
2. CO3____
6. PO4____
10. S____
14. P____
3. O___
7. Ca____
11. SO4____
15. F____
4. Li____
8. Br____
12. N____
16. Na____
Section 3: Below are several ionic compounds. Write the chemical formula of the following ionic compounds containing
polyatomic ions, main group and transition metals. Use the roman numeral to determine the oxidation state of any
transition metal. Remember the overall compound must be neutral!
1. Ammonium phosphate ___________
8. Aluminum sulfite _____________
2. Iron(II) oxide _____________
9. Potassium permanganate__________
3. Iron(III) oxide _____________
10. Zinc nitrate _____________
4. Calcium chloride_____________
11. Sodium chloride_____________
5. Aluminum sulfide_____________
12. Magnesium oxide_____________
6. Copper(II) sulfate _____________
13. Sodium carbonate_____________
7. Lead (IV) chromate_____________
14. Cobalt (II) nitride_____________
Section 4: Below are several acids. Use the criss-cross method to determine the chemical formulas of each. Remember
you need to recognize whether they are binary or ternary first!
1. Phosphorous acid: _______
4. Phosphoric acid: _______
2. Hydroflouric acid: _______
5. Carbonic acid: _______
3. Hydrochloric acid: _______
6. Sulfuric acid: ________
Formula Writing Practice – Level 2 (Intermediate)