Cotocollao: punto de encuentro interétnico en el noroccidente de Pichincha

I am going to ask you some questions about what you did while you were solving the chemistry problems which were given to you.

Planning

1. Did you always read the whole problem first before attempting to solve it? Why was this important/not important? 2. Do you sort out the information (into relevant and irrelevant) given in the

problem? Why is this necessary/ unnecessary during problem-solving? 3. Describe the steps you would follow when solving a wordy (or long) problem. 4. When solving a numerical problem how do separate relevant from irrelevant

data? (Possible response: I look at what the question requires me to calculate and then I choose the appropriate formula to use which helps me to identify the relevant data).

Monitoring

1. How often did you revise your solution as you worked through the problem? Can you give an example of when you did this and when you did not do this? 2. When solving a numerical problem it is necessary to check your steps as you

work through the problem. How often do you do this? Give me example of when you did this and did not do this.

3. Did you always rate the difficulty of the problem e.g. this problem is hard/easy? Why was it important to do this?

4. Did you question yourself whether you are using the correct method while solving the problem? Explain why you did/did not do this.

Control

1. Do you think of a method to solve a problem before you attempt solving it? 2. How did you test the selected method to see if it was suitable for the problem

task? How did you do this?

3. What did you do when you find out that you are using the wrong method? 4. Did you always ask other students or the teacher when you didn’t know how

to solve a problem? Explain Evaluation

1. How do you check the effectiveness of your method?

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3. How do you know that a solution is correct or wrong? 4. Why is it important to revise your procedure/method?

Motivation

1. How many of you believe that stoichiometry is difficult? Did you find the problem tasks difficult? (expectancy/affective)

2. Did you find the problem tasks interesting or boring? (Don’t tell me what you think I want to hear. Tell me the truth). Explain(value).

3. Do you feel frustrated when you can’t figure out how to approach a problem- solving task? (affective)

4. What do you do when you feel frustrated? (affective)

194 Appendix 5

Teachers’ semi-structured interview questions

1. So how long have you been teaching the chemistry group that I have been working with?

2. Did you teach them stoichiometry?

3. Can you just talk me through how you teach stoichiometry i.e. what’s your approach and how do you develop the topic?

4. Do you teach students to follow an algorithm? 5. Do you emphasize on conceptual understanding?

6. Do you advise students to remember the equations and to look at the interconnection between these equations?

7. Do you ask students to read the question and extract relevant information? 8. Do you advise students to stop and think (while solving a problem) if they are

using the correct formula or the correct method

9. Do you encourage students to work together or to ask the teacher if they are in doubt or if they are stuck?

10. Do you deliberately combine students with different abilities to exploit joint cognition?

195 Appendix 6 PRE-TEST PROBLEM-SOLVING TASK

20 grams of magnesium carbonate react with 25cm³ of hydrochloric acid at room temperature and pressure. Magnesium carbonate, is an inorganic salt that is a white solid. Several hydrated and basic forms of magnesium carbonate also exist as minerals. Magnesiumcarbonate is ordinarily obtained by mining the mineral magnesite. Magnesium carbonate can be prepared in laboratory by reaction between any soluble magnesium salt and sodium bicarbonate:

MgCl2(aq) + 2NaHCO3(aq) → MgCO3(s) + 2NaCl(aq) + H2O(l) + CO2(g)

a) Write a balanced equation for the reaction

b) Describe and explain what is observed during the reaction

c) Calculate the number of moles of magnesium carbonate that reacted

d) A gas is formed during the reaction, calculate the volume of the gas formed during reaction.

e) Calculate the mass of the salt formed in this reaction f) Estimate by calculation the concentration of the acid.

196 Appendix 7

Teachers’ practice problem-solving task

Instructions to the teacher of the experimental group

1. Teacher to introduce the metacognitive framework as a problem-solving aid. 2. Each student is given a copy of the metacognitive framework

3. Teacher to discuss with the students how to use the metacognitive framework to solve stoichiometry problems.

4. As the instructions on the metacognitive framework are self-explanatory, the teacher uses problem below to demonstrate to students how to use the metacognitive framework.

Practice chemistry problem

Potassium chlorate is an odourless, solid, fine crystalline, white coloured material. A word of caution about potassium chlorate is in order however. This material is a powerful oxidizing agent and used in making explosives, matches, and pyrotechnics. Oxygen gas can be produced by decomposing potassium chlorate using the reaction below. If 138.6 g of KClO3 is heated and decomposes completely.

KClO3 (s) ---> KCl (s) + O2 (g)