Identity Persists
Identity persists explains that an atom's chemical identity does not change during a reaction—an oxygen atom remains oxygen even after becoming part of a new molecule like rust. In Amplify Science (California) Grade 7, Chapter 2: Reactions, students learn that chemical changes alter only how atoms are grouped, not what the atoms themselves are.
Key Concepts
The identity of an atom is permanent during a reaction. An oxygen atom in the water remains an oxygen atom when it becomes part of rust.
The change occurs only in how the atoms are grouped.
Common Questions
Do atoms change their identity during a chemical reaction?
No, atoms keep their chemical identity during a reaction. An oxygen atom remains oxygen whether it is in water, in rust, or in air. Only the groupings and arrangements of atoms change.
What changes during a chemical reaction if atoms don't change?
During a chemical reaction, atoms rearrange into new groupings called molecules or compounds. The macroscopic substance changes (e.g., iron becomes rust), but each individual atom remains the same type.
How does identity persistence support the Law of Conservation of Matter?
Since atoms never change their identity and are never created or destroyed, the types and numbers of atoms must be the same before and after a reaction. This is why mass is conserved in chemical reactions.
Where is identity persistence covered in Amplify Science Grade 7?
Identity persists is covered in Amplify Science (California) Grade 7, Chapter 2: Reactions.