Free Molecular Formula And Valency Lesson Plan for 7th Grade Students

Topic: Molecular formula and Valency

Objectives & Outcomes

• Students will be able to define molecular formula and understand the relationship between molecular formula and chemical formulas.
• Students will be able to use valency to calculate the number of atoms or molecules in a given compound.

Materials

• Whiteboard and markers
• Handouts with examples of chemical formulas and molecular formulas
• Calculators (optional)

Warm-up

• Review the concept of chemical formula by showing students examples of chemical formulas and asking them to identify the elements present in each compound.
• Then, introduce the concept of molecular formula and explain that it is the same as chemical formula, but it describes the number of atoms in a molecule instead of a single atom.

Direct Instruction

• Show students examples of molecular formulas and ask them to identify the elements present in each molecule.
• Then, introduce the concept of valency and explain that it is the number of atoms that an element can form bonds with.
• Using the periodic table, show students how to determine the valency of an element by looking at the number of valence electrons in the element's outermost energy level.
• Using the molecular formula, show students how to make a formula for a molecule using valency.

Guided Practice

• Have students work in pairs to solve a series of problems using the concept of valency and the periodic table. Solutions can be checked using the periodic table and the formula calculator.
• Allow a few minutes for students to work on the problems and then have them share their solutions with the class.

Independent Practice

• Divide students into small groups and give each group a list of chemical compounds and their molecular formulas.
• Students must use the periodic table and the concept of valency to determine the chemical compounds and their molecular formulas.
• Allow students to work on the problem for a set period of time, and then have them present their solutions to the class.

Closure

• Review the concept of molecular formula and valency in depth.
• Ask students to provide examples of chemical compounds and their molecular formulas from the independent practice activity.

Assessment

• Observe students during the guided practice and independent practice activities to assess their understanding of the concept of molecular formula and valency.
• Collect and review the worksheets and other independent practice activities to assess their ability to apply the concept of molecular formula and valency.