Razumevanje kemijskih pojmov na submikroskopski ravni pri učencih devetega razreda osnovne šole

Slapničar, Miha (avtor), Tompa, Valerija (avtor), Glažar, Saša (avtor)

Submikroskopske predstavitve so učencem težje razumljive, kar je posledica abstraktnosti delčne narave snovi. Rezultati raziskav potrjujejo omenjeno trditev, saj imajo učenci razvita napačna razumevanja kemijskih pojmov na submikroskopski ravni. Namen raziskave je bil ugotoviti, ali imajo učenci devetega razreda osnovne šole razvita napačna razumevanja kemijskih pojmov: agregatno stanje snovi, zmes, čista snov, element, spojina, fizikalna in kemijska sprememba ter kemijska reakcija na submikroskopski ravni. V vzorec raziskave je bilo vključenih 188 učencev devetega razreda šestih osnovnih šol iz Ljubljane in okolice. Merski inštrument raziskave je predstavljal preizkus znanja s petimi avtentičnimi problemskimi nalogami. Preizkus znanja je ekonomičen, vsebinsko veljaven ter diskriminativen. Rezultati raziskave kažejo, da ima 48,4 % učencev devetega razreda težave pri prepoznavanju submikroskopske predstavitve spojine. 67,0 % učencev ne loči med submikroskopskima porazdelitvama delcev v trdnem in tekočem agregatnem stanju vode. Več kot 75,0 % učencev iz submikroskopskih predstavitev prepozna zmes, čisto snov in fizikalno spremembo. 99,5 % učencev je uspešnih pri prepoznavanju elementa iz shem porazdelitve delcev. Glede na rezultate raziskave je mogoče skleniti, da učenci devetega razreda na submikroskopski ravni zamenjujejo porazdelitev delcev v tekočem in trdnem agregatnem stanju vode, ker še ne poznajo povezovanja molekul vode z vodikovimi vezmi. Večina učencev devetega razreda (88 %) iz submikropredstavitve reaktantov in produktov pri enostavni kemijski reakciji ni uspešno zapisala enačbe kemijske reakcije. V osnovni šoli bi bilo pri spoznavanju kemijskih pojmov in procesov za njihovo boljše razumevanje potrebno večje povezovanje makroskopske, submikroskopske in simbolne ravni predstavitve kemijskih pojmov.

• Jezik: Slovenski jezik
• Ključne besede: makroskopska raven
• Vrsta gradiva: Drugo
• Tipologija: 1.08 - Objavljeni znanstveni prispevek na konferenci
• Organizacija: PEF - Pedagoška fakulteta
• Leto izida: 2016
• Št. strani: 1007-1021
• PID: 20.500.12556/RUL-88644
• COBISS.SI-ID: 11407689
• Datum objave v RUL: 30.08.2017

Sekundarni jezik

• Jezik: Angleški jezik
• Naslov: Understanding of chemical concepts at the sub-microscopic level of the ninth grade students of elementary school

Izvleček

Sub-microscopic representations are more difficult to understand for pupils, which is due to the abstraction of the particle nature of matter. The research results confirm the above argument, since pupils misunderstand the chemical concepts at the sub-microscopic level. The purpose of the study was to determine whether the ninth graders misunderstand the chemical concepts such as the aggregate state of matter, a mixture, a pure substance, an element, a compound, a physical and a chemical change, and a chemical reaction at the sub-microscopic level. The survey sample included 188 ninth graders of six elementary schools in Ljubljana and its surroundings. The measurement instrument of the survey was the knowledge test with five authentic problem tasks. The knowledge test is economical, has content validity and is discriminatory. The survey results show that 48.4% of the ninth graders have difficulties in identifying the sub-microscopic representation of a compound. 67.0% of the pupils do not distinguish between the sub-microscopic distribution of particles in the solid and liquid states of water. More than 75.0% of the pupils recognize a mixture, a pure substance and a physical change from sub-microscopic representations. 99.5% of the pupils are successful in identifying individual elements of the particle distribution schemes. According to the research results it can be concluded that the ninth graders confuse the distribution of particles in the liquid and solid states of water at the sub-microscopic level, as they are not yet familiar with the hydrogen bonding of water molecules. The majority of the ninth graders (88%) failed to write down the equation of a chemical reaction from a sub-microscopic representation of reactants and products. In elementary school, when teaching chemistry concepts and processes, greater integration of the macroscopic, the sub-microscopic and the symbolic levels of representations of chemistry concepts would be essential a for better understanding of the chemistry concepts and processes.

• Ključne besede: macroscopic level