Laboratory Activities

Unit Overview

This unit is intended to be integrated with the other units in Chemistry 20, rather than being treated separately. The laboratory activities should be spread through the entire course, although one or two units may receive a greater allotment of laboratory activity time than the others. They should also target a wide range of factors within all seven Dimensions of Scientific Literacy.

The 20 hours of laboratory activity should be time that students spend actually performing activities. Laboratory activities can be considered as having three separate phases: the preparation phase, the activity itself, and follow-up phase. Demonstrations performed by the teacher should not be counted as part of the time devoted to laboratory activities, unless they involve a significant response and self-directed extension of the experience by the students.

Some of the activities may be more open-ended than others. Students should be encouraged to design and conduct their own investigations, when appropriate. Many activities are correlated to the topics of the curriculum in Science: An Information Bulletin for The Secondary Level - Chemistry 20/30 Key Resources.

Consideration should be given to the use of microscale experimentation. In an article in Chem13 News on microscale experimentation, Geoff Rayner-Canham, William Layden and Deborah Wheeler wrote:

There are eight advantages of conversion to microscale.

1. The low cost of most microscale equipment. Many items are available in bulk from biomedical suppliers.

2. A reduction in chemical costs (though there is a short term increase in costs due to the purchase of microscale equipment).

3. An almost complete elimination of waste disposal problems.

4. A reduction in safety hazards. Not only are smaller quantities likely to present less severe safety hazards, but the use of plasticware precludes the possibility of injury due to broken glass.

5. Most experiments can be performed more quickly on the microscale.

6. Less space will be needed for storage as the volume of chemicals will be less. Also, the space needed for equipment storage is far less.

7. The microscale (twenty-first century) lab can be a clean, odourless, comfortable work environment in contrast to the cluttered, dirty, smelly, and dingy (nineteenth century) laboratory of the past.

8. Students really enjoy working with microscale equipment.

(from CHEM13 NEWS, #199, December 1990, page 8. Used with permission.)

More information on microscale experimentation can be found in Chem13 News February 1989 (#183), March 1989 (#184), January 1991 (#200), February 1991 (#201), and September 1991 (#205).

"Microscale Chemistry Experimentation for High Schools - Part II: Home Made Equipment" by Geoff Rayner-Canham, Deborah Wheeler and William Layden (CHEM13 NEWS, #200, January 1991) and "Iron:Copper Ratios, A Micromole Experiment" by Jacqueline K. Simms (CHEM13 NEWS, #200, January 1991) are included as Appendix 1 in this Guide.

Teachers should attempt to use a variety of student assessment techniques during the laboratory activities. Included among those should be techniques which can be used to obtain information in the psychomotor and affective domains. Rating scales, observational checklists, anecdotal records, and test stations could be included. If students are performing tasks which can not be done with pencil and paper, then it is not appropriate to base their assessment on the results of pencil and paper tests alone.

Factors of scientific literacy which should be emphasized

• A1 ..........public/private
• A3 ..........holistic
• A4 ..........replicable
• A8 ..........tentative
• A9 ..........human/culture related

• B1 ..........change
• B2 ..........interaction
• B9 ..........reproducibility of results
• B10 ..........cause-effect
• B13 ..........energy-matter

• C2 ..........communicating
• C3 ..........observing and describing
• C4 ..........working cooperatively
• C5 ..........measuring
• C6 ..........questioning
• C7 ..........using numbers
• C8 ..........hypothesizing
• C9 ..........inferring
• C10 ..........predicting
• C11 ..........controlling variables
• C12 ..........interpreting data
• C15 ..........analyzing
• C16 ..........designing experiments
• C19 ..........consensus making
• C20 ..........defining operationally

• D2 ..........scientists and technologists are human
• D3 ..........impact of science and technology
• D6 ..........resources for science and technology
• D7 ..........variable positions
• D8 ..........limitations of science and technology

• E1 ..........using magnifying instruments
• E3 ..........using equipment safely
• E7 ..........manipulative ability
• E11 ..........measuring mass
• E12 ..........using electronic instruments

• F2 ..........questioning
• F3 ..........search for data and their meaning
• F5 ..........respect for logic
• F7 ..........demand for verification

• G1 ..........interest
• G3 ..........continuous learner

Foundational Objectives for Chemistry and the Common Essential Learnings

Acquire concrete experiences of chemical events which form the basis for abstract understandings.

Gain proficiency in manipulating laboratory equipment.

Strengthen understanding within chemistry through applying knowledge of numbers and their interrelationships. (NUM)

Develop a contemporary view of technology. (TL)

Develop compassionate, empathetic and fair-minded students who can make positive contributions to society as individuals and as members of groups. (PSVS)