Chemistry Basics

• Classify matter by properties, states, and changes.
• Use units, tools, repeated trials, and safety rules during investigations.

Practice: Sort examples as physical or chemical changes and explain the evidence for each choice.

• Use atomic number, mass, protons, neutrons, and electrons.
• Read periodic-table patterns for groups, periods, and properties.

Practice: Interpret five element cards and explain one pattern across a group or period.

• Distinguish atoms, molecules, compounds, and mixtures.
• Use simple formulas to count atoms and describe composition.

Practice: Model three compounds with drawings and count each element in the formula.

• Identify signs of chemical reactions.
• Use conservation of matter to reason about reactants and products.

Practice: Analyze a simple reaction model and explain why atoms are rearranged, not destroyed.