Hana Cídlová

HIDDEN RISKS OF (SCHOOL) CHEMICAL LABORATORY

The article deals with a quite usual laboratory activity – pipetting. This method of measuring the volume of liquids appears to be relatively safe in comparison with other chemical operations. But, on the other hand, the use of classical glass pipettes is connected with many security and health risks. The usual chemical hazards associated with inhalation of the pipetted substance or its intrusion into the mouth are repeatedly mentioned to the pupils and students and they are trained to prevent these situations. However, the health risks associated with the use of glass pipettes are being nearly never mentioned at schools, and that is why Czech pupils and students are aware of them only exceptionally. In the introduction to our article we explain the safety risks and health risks, advantages and disadvantages associated with different pipetting methods. Afterwards, we do analyze the results of a questionnaire survey between the students of chemistry teaching, focused on their favorite pipetting method and reasons to their decision. The last part of our research is the analysis of the results of different methods of pipetting carried out by the 3rd grade students of chemistry teaching at Faculty of Education, Masaryk University, Czech Republic. The analysis is focused on the correctness of pipetting (mean value of the pipetted volume) and accuracy of pipetting (relative standard deviation in repeated pipetting of the same volume).

DO THE PUPILS AND STUDENTS UNDERSTAND ELECTROCHEMICAL VOLTAGE SERIES

This article is focused on chemical skills and their applications in the field of electrochemistry. The main problem is the application of electrochemical voltage series on solving of practical problems. The article compares the results received with university students (future teachers of chemistry) in their last year of study with the results received with lower secondary school pupils and upper secondary school pupils. It follows from our results that only 1/3 of university students of chemistry teaching in the last year of their study does understand the rules of electrochemical voltage series. Similar situation is with upper secondary school students. As for lower secondary school, according to our results the children must be taught some “cookbook procedure”. They do not know the rules how to use the electrochemical voltage series, they do not even recognize the rules among other possibilities. But they do correctly solve tasks that require application of the rules. How do they do it? They can not learn it from their textbook, as the subject matter is not explained very well there. Maybe their teachers tried to teach them how to use the electrochemical voltage series, but they did not connect his/her explanation with the text in the textbook. This situation is very sad, as electrochemical voltage series gives a great opportunity to explain why some substances do react one with the other, and why other substances do not. Instead, many children only memorize the reactions, beginning to hate chemistry because of too much subject matter. The DOI number of the abstract on the conference pages is: http://dx.doi.org/10.21125/edulearn.2017.2275

Klesají znalosti a dovednosti žáků i v jejich zájmové činnosti

Turistickeho zavodu, pořadaneho Klubem ceských turistů, se každorocně ucastni několik set děti i dospělých. Přestože jeho zakladem je terenni běh, nezanedbatelnou roli hraji dalsi soutěžni ukoly, např. poznavani dřevin, poznavani turistických a topografických znacek, kulturně-poznavaci cinnost, prace s mapou a buzolou nebo odhad vzdalenosti v terenu. Atmosfera zavodů je pro zvladnuti uvedených ukolů velmi silně motivujici. V přispěvku je rozebrana uspěsnost zavodniků dětských kategorii při řeseni vybraných přirodopisných a zeměpisných ukolů v Ceskem poharu Turistickeho zavodu za roky 2008-2016. Je vypozorovana klesajici uroveň znalosti a dovednosti žaků i při jejich zajmove cinnosti.

The Relevance of Health and Environmental Education in Chemistry for Pupils of Czech Secondary Schools and School-leavers

Abstract The aim of the authors of this article was to find out how much importance Czech pupils and school-leavers who are not professionally engaged in chemistry attach to those topics of Health and Environmental Education included among the obligatory outcomes in Chemistry for Lower Secondary Schools. The research was carried out by means of a questionnaire administrated to 576 pupils aged 14-18 years and 122 school-leavers people with finished education). The conclusion was that as for subjective respondents’ opinion on the importance of learned skill outcomes, the respondents preferred topics of Health Education to those of Environmental Education. Moreover, the authors have found that the interest in prevention and first aid increases with growing age of the respondents. The pupils’ interest in environmental topics is very low. On the contrary, school-leavers show an overwhelming interest in chemistry of nutrition and in environmental protection. This discrepancy should probably be solved by better motivation of pupils in the future.