reaction velocity

Prague, 27 and 28th August 2011

Carlos Cunha, E. Sec. Dom Manuel Martins, Setúbal, Portugal

Summer School, Prague, 2011

• Name: Reaction Velocity

• Subject Area: Chemistry

• Age of Students: 13-15

• Topic: Chemical Reactions

• Content involved: Chemical reactions velocity

Good Practice description


• Content involved: Chemical reactions velocity

• Skills (student skills) involved: Observation, Laboratory/Hand´s-on, autonomy,

solving problems, interpretation, math & computer use.

• Aims:

– Help students understand a chemical reaction evolution;

– Determination of the reaction velocity from the mass versus time graphic.

• Duration: 2 x 90 minutes

Methodological aspects (1/2)

• How to launch activities and raise student’s interest

� Activity begins with the movie presentation: http://www.youtube.com/watch?v=7VeGnJmIjxs

� http://www.youtube.com/watch?v=KI1BJL3bg1M

� The experiment will use current materials and reagents like ”vinegar” and ”backimg powder”;


”backimg powder”;�Does the concentration influence reaction velocity

•How to organize students (individual work, pairs, larger groups, different ways at different moments … )

�Large group for movie presentation and discussion;�Working in pairs to prepare the experiment apparatus;�Working in pairs to make the graph mass vs time;�Final discussion in large group.

Methodological aspects (2/2)

Resources needed (equipment, software, manipulative, text, video, websites, …)

Vinegar;

Backing powder;

Two small PET bottle;

Graph paper;

Scale (it can be a kitchen scale);


Scale (it can be a kitchen scale);

Computer with Excel (not mandatory).

Specific strategies to keep students engaged

Students will be asked to be involved in all activities, either by seeing movies

and demonstrations, or by constructing their material and do their own

measurements.

• A detailed description of how to proceed: sequence of tasks in a chronological

order including indication of time spent on each task

– Theme presentation using a YouTube movie (aprox. 5 min);

– Discussion about scale and how to make registrations (aprox. 15 min);

– Experiment preparation (aprox. 15 min.);

– Record the mass evolution during reaction, using a cell phone (aprox. 20 min.);

Detailed description of how to proceed


– Record the mass evolution during reaction, using a cell phone (aprox. 20 min.);

– Play the movie, frame by frame and make the time versus mass table (aprox.

20 min);

• A detailed description of how to proceed: sequence of tasks in a chronological

order including indication of time spent on each task

– Construction of a graphic on graph paper, using mass vs time (aprox. 40 min.);

– Repeat procedure with another reagents concentration (aprox. 20 min.);

– Replication of the activity using spreadsheet application (aprox. 30 min.).

Lab material and reagents


Material and reagents Initial mass

Students Implementation (1/2)


Weighing of baking powder Transferring vinegar

Students Implementation (2/2)


Mixing the reagentsObserving the reaction

Experimental results


Teachers who implemented the GP

• Anja Buntrock, Finland

• Carlos Cunha, Portugal

• Filipa Silva, Portugal

•Malgorzata Zajaczkowska, Poland


•Malgorzata Zajaczkowska, Poland

•Monika Bartova, Czech Republic

Create EUN/SPICE account

http://www.scientix.eu/


http://moodle.scientix.eu/



spices

Can this GP be implemented on your country?

How can this GP be implemented on your


How can this GP be implemented on your

country?


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reaction velocity

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