Physical Science

Evaporation

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Standard Statement:
3.4.4 A -  Know basic concepts about the structure and properties of matter.

Content Objectives:
Students will be able to:

Know the difference between chemical and physical properties and the difference between chemical and physical change.

Process Objectives:
Students will be able to:

1.   Identify the state of matter of various substances.

2.   Observe the transition between various states of matter.

3.   Recognize the difference between a chemical and a physical change.

Give students a scratch-n-sniff sticker on a piece of paper.  As a performance based assessment they should scratch it and describe what happens in words and pictures.  Score according to the rubric.  (Attachment 1)

Option A

On a cotton ball, soak various liquid extracts or solid smelly substances dissolved in water.  Place in a sealed Ziploc bag.

Option B

Prepare this ahead of time – do not allow students to use needles.

In a hypodermic needle (such as those used for insulin shots) place various extracts.  Insert the needle and extract into the back of bubble wrap.  Close the hole with clear tape.

Actual Procedure

In groups, students break the bubbles open by popping them OR open the Ziploc bags and use their hands to waft the smell to their noses.  Through this process, safety is stressed in not smelling unknown substances directly.  Switch bubble wrap or Ziploc bags with other groups.  Discuss correct identification of each smell.

Lead into a whole group discussion that explains the chemical and physical changes and states of matter.  The solid bubble wrap or cotton ball is filled or soaked with a liquid is exposed, some of it is turned into a gas.  This is called evaporation and is a physical change.  As material evaporates, it reaches the nose where chemical changes take place in special receptors.  The receptors send a message to the brain which tells you what the smell actually is.  For closure, relate this activity to scratch-n-sniff stickers that have containers glued on to them and work under the same principle.  List other things that relate this concept to everyday life.  Have students brainstorm.

www.chem.uci.edu/education/undergrad_pgm/
applets/sim/simulation.htm

Kathy Schrock’s Guide for Educators

Suggested Level:
Grades 3-4

Standard Category:
3.4 – Physical Science, Chemistry and Physics

Materials:
Water

Solid smelling substances (i.e. Cinnamon, nut meg.)

Liquid extracts

Ziploc bags and cotton balls or bubble wrap, clear tape and hypodermic needles

Scratch-n-Sniff stickers

Instructional Strategies:
Use of manipulatives Performance-based assessment

Hands-on activity

Cooperative and individual learning

Whole class discussion

Inquiry approach

Related Concepts:
Inquiry and formulation of a hypothesis

Make a terrarium to represent the water cycle

Attachment 1

Scoring Rubric

Standard Category:   3.4.4 A                                                                                 Standard Grade Level:   4

Standard Statement:  Recognize basic concepts about the structure and properties of matter.

Process Objective:  Performance-Based Assessment with scratch-n-sniff sticker

Title of Task:  Evaporation