Physical vs. Chemical Change Activity
Teacher Notes:
Benchmark: Draw pictures to distinguish the relationships between atoms in physical and chemical changes
Synopsis: In this activity students are presented with visual pictures of a physical and chemical change and then
produce their own diagrams from written physical and chemical reactions.
Physical Change Diagram.
Several diagrams of physical change are presented to students. Solid : packed together orderly molecules
(represented by combinations of suits in cards) producing liquid or gas randomly scattered Next a diagram of a
pyramid of molecules goes through a physical change to produce individual molecules and smaller pyramid of
molecules. Then students are given a written description of a physical change and they will draw a picture to
describe the physical reaction..
Chemical Change Diagram.
Atoms of elements are represented as suits in cards: heart, spade, club & diamond. The teacher will guide the
students in an atom survey of each set of diagrams to determine: products, reactants, number of each kind of
atom of reactant molecules and each kind of atom of product molecules. The teach will then guide the student
to determine the correct number of molecules – coefficients. Next the students are given a written equation and
they will draw a diagram of the chemical reaction
Physical Change vs Chemical Change
Students are given written description of two reactions: a physical change and a chemical change. Students will
then draw each reaction and identify each type of reaction. Then the students will write a description of each
reaction and how they are different and alike.
Purpose: Gain knowledge to distinguish physical and chemical change
Materials: Diagrams of physical and chemical reaction & student coordinated diagrams copies.
Procedure:
Given the following diagram,
1) identify and label reactant and product molecules.
2) do an atom survey of given reactant and product molecules
3) Write a balanced equation from the diagram.
Diagram I
♠-♠
♦-♦ 
♠-♠ +
♠-♦-♠
♠-♦-♠
Explantion
Balanced equation
2 ♠-♠ + ♦-♦  2 ♠-♦-♠
reactants
products
Chemical Change
The reactant molecules rearrange into new product molecules.
Diagram II
♠-♠ ♠-♠
♠-♠
♠-♠

♠-♠
♠-♠
♠-♠
♠-♠
Student ‘s Reponse Physical Reaction
Molecules are close together then farther apart – change of distance. There is no rearrangement of atoms
from reactant molecules to product molecules.
Diagram III
♥
♥
♥
♥
+
♠-♠

♥-♠-♥
♥-♠-♥
Student’s Response Chemical Change
4 molecules H combine with 2 molecules ♠- ♠ to form 2 molecules of ♥-♠-♥
The atoms of reactant molecules rearrange into new molecules.
Diagram IV
♠- ♥
♠- ♥
♠- ♥
♠-♥

♠- ♥ ♠-♥
♠-♥
♠- ♥
Student Response Physical Change
4 molecules of ♠-♥ spread apart with greater space between each molecule—no rearrangement of atoms in
molecules.
Diagram V
♦-♥- ♦ ♦-♥-♦
+
♣-♣ 
♦-♣-♦ ♦-♣-♦
+
♥-♥
Student Response
2 molecules ♦-♥-♦ combine with one molecule to form 2 molecues of ♦-♣- ♦and one molecule ♥-♥.
Chemical reaction. The reactant molecules rearrange into new product molecules.
Student Assigment
Given
♠-♠
+
♣-♥-♣
♣-♥-♣

♣-♠-♣
♣-♠-♣ +
♥-♥
Chemical Reaction
1 ♠-♠ and 2 ♣-♥-♣  2 ♣-♠-♣ and 1 ♥-♥
The reactant molecules rearrange into the product the molecules.
Given
Diagram VI
♣-♠
♣-♠
♣-♠
♣-♠

♣-♠
♣-♠
♣-♠
♣-♠
Student reponse
Physical Change.
4 reactant molecules spread out. No rearrangement of atoms in molecule.
3 molecules of ♣-♠ spread out