Practice recognizing the seven diatomic elements, writing their correct molecular formulas, and applying them in simple chemical equations.
Read each problem carefully. Write complete answers and show your work when balancing equations.
Identifying and writing formulas for the seven elements that exist as diatomic molecules
Chemistry - Grade 9-12
- 1
List the seven diatomic elements by name and write the correct chemical formula for each one.
- 2
A student writes elemental oxygen as O in a chemical equation. Explain what is wrong and write the correct formula.
- 3
Circle or identify which formulas represent diatomic elements: H2, He, N2, Na, Cl2, CO2, Br2.
- 4
Write the formula for elemental chlorine and explain why the subscript is needed.
- 5
Balance this equation for the formation of water: H2 + O2 -> H2O.
- 6
Balance this equation for the formation of hydrogen chloride: H2 + Cl2 -> HCl.
- 7
A periodic table diagram highlights hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine, and iodine. What do these highlighted elements have in common?
- 8
Decide whether each formula is correct for the element in its natural elemental form: F2, I, O2, Br, N2. Rewrite any incorrect formulas.
- 9
Explain the difference between the symbol N and the formula N2.
- 10
Balance this equation for the formation of magnesium bromide: Mg + Br2 -> MgBr2.
- 11
A student claims that all gases are diatomic elements. Use examples to explain why this claim is incorrect.
- 12
Classify each substance as a diatomic element, a monatomic element, or a compound: O2, Ne, H2O, Cl2, Na, CO2.