Symbols Formulas and Earth

Overview

In this second lesson of “Elements, Compounds, and Change,” students connect familiar elements to their chemical symbols and use simple formulas to represent compounds. They then apply the idea that matter is made of elements by sequencing Earth’s four layers and identifying that different materials and elements are found throughout Earth.

Learning intentions

Students will be able to:

• Identify common elements by their names and chemical symbols.
• Match simple compounds with their chemical formulas.
• Sequence and label Earth’s crust, mantle, outer core, and inner core.
• Explain that Earth’s layers contain matter made from different elements and substances.

Success criteria

• I can match an element name to its correct symbol.
• I can match a compound to a simple chemical formula.
• I can correctly order and label the four layers of Earth.
• I can describe one way elements or matter are found in Earth.

Curriculum links

• Identify elements on the periodic table as metals, nonmetals, metalloids, and rare Earth elements based on physical properties and importance to modern life.
• Investigate physical properties of matter and distinguish pure substances, solutions, and heterogeneous mixtures.
• Compare solids, liquids, and gases in terms of structure, shape, volume, and particle kinetic energy.
• Identify evidence of a possible chemical change, including gas production, thermal energy change, precipitate formation, or color change.

Lesson structure (30 minutes)

1. 0–4 min · Hook and review. Teacher displays the opening Earth image and mystery question: “What kinds of matter might be inside Earth?” and briefly reviews that all matter is made of atoms and that elements have names and symbols. Students make a quick prediction and name any element symbols they recognize, such as H, O, C, or Fe.

2. 4–9 min · Model symbols and formulas. Teacher uses the symbol and formula teaching slides to model that an element symbol represents one type of element, while a formula shows which elements are present in a compound; model H for hydrogen, O for oxygen, and H₂O for water. Emphasize that the small number shows how many atoms of that element are represented, not the element’s charge or an equation. Students use fingers or colored counters to show two hydrogen atoms and one oxygen atom in H₂O, then explain what the symbols mean.

3. 9–16 min · Partner matching investigation. Teacher places students in six pairs and one triad, distributes the symbols, formulas, and Earth layers activity sheet, and provides each group with prepared color-coded symbol/formula cards; teacher displays the matching instructions and examples. Students match element names to symbols and simple compound names to formulas, including hydrogen/H, oxygen/O, carbon/C, iron/Fe, water/H₂O, and carbon dioxide/CO₂. Each group records two matches and explains one match to a nearby group.

4. 16–23 min · Earth layer sequence. Teacher shows the cutaway Earth diagram and layer prompts and explains that Earth can be described as four major layers: crust, mantle, outer core, and inner core. Students work together to sequence and label the four layers on the worksheet, placing the crust on the outside and the inner core at the center. They discuss which layers are solid or liquid at this level of study and identify that each layer is matter made of atoms and elements.

5. 23–27 min · Connect symbols to Earth. Teacher asks, “Why might scientists use symbols and formulas when describing Earth materials?” and records student ideas on the board; teacher revisits the Earth, matter, and elements discussion slide. Students write one sentence using the frame “Earth contains matter made of ___, and scientists use ___ to represent it.” Accept responses such as elements, symbols, or formulas, while clarifying that a symbol represents an element and a formula represents a compound.

6. 27–30 min · Exit check. Teacher displays the three-question plenary slide and asks students to complete the final section of the individual exit check without partner help. Students answer: “Write the symbol for oxygen,” “What does H₂O represent?” and “Put the Earth layers in order from outside to inside.” Collect the sheets to identify misconceptions for the next lesson.

Resources

• the Symbols, Formulas, and Earth slide deck
• the symbols, formulas, and Earth layers worksheet
• Prepared color-coded element and compound matching cards
• Colored counters or small linking cubes
• Periodic tables suitable for Grade 6
• Projector or interactive display
• Whiteboard and markers
• Pencils and colored pencils

Assessment

• Listen during partner matching for accurate use of “element,” “symbol,” “compound,” and “formula”; ask students to justify matches rather than guess.
• Check the worksheet Earth diagram for correct sequence and labels, and question students who place the mantle or core layers incorrectly.
• Use the three-question exit check to assess symbol recognition, formula interpretation, and Earth layer sequencing.

Differentiation

• Provide a reference strip with element names, symbols, and color cues; read directions aloud and model one complete match before students begin.
• Offer sentence starters: “The symbol ___ stands for ___,” “The formula ___ contains ___,” and “The ___ is closest to Earth’s surface.”
• Pair students strategically and allow students to demonstrate understanding by pointing, arranging cards, drawing, or speaking instead of writing every response.
• For students ready for extension, ask them to explain how H₂O differs from H and O and why a compound’s formula includes more than one element. Provide enlarged print, reduced visual clutter, and extra processing time for students with reading, attention, or fine-motor needs.