Peter, in Y7 told me that gases ‘try’ to fill up a room or container. His use of ‘try’ is anthropomorphic, because to try is to deliberately set out to achieve something. Gases are not conscious agents, and do not try to do things. Peter was able to suggest something he might try to do, and when asked realised that he had ‘phrased that wrong’. Yet as the conversation proceded he immediately reverted to how a gas would ‘try’ to get out of a bottle.

Clearly for Peter this was just a figure of speech rather than a belief that the gas was actually trying to do anything – we can call this an example of ‘weak’ anthropomorphism (Taber & Watts, 1996). It may seem that as Peter was aware this was just used figuratively, it is not something that should concern the science teacher. However, it was also clear that his use of this way of talking had become habitual, as he so readily used this type of language.

The use of figurative language is not to be discouraged in itself – indeed it has an important role in science and science learning. However, such language can readily come to stand in the place of any deeper understanding of phenomena. Gases do fill out containers, but not because they want to. Yet if we have a ready language for talking about such phenomena which uses anthropomorphism as a pseudo-explanation (something which has the form of an explanation – e.g. because gases try to expand to fill a container – without actually offering real reasons), we may not actively seek or be alert to a deeper level of explanation (such as the intrinsic motion of quanticles – the molecules in the gas). As it is counter-intuitive that gas molecules could have intrinsic and indefinite motion, the analogy with human behaviour (gases try to fill containers as we try to type without looking at the keyboard) may continue to be used even after the scientific model has been taught.

P: Gases, they try and fill whole room, they don’t, like liquids, they stay at the bottom of the container, but gases go fill, do everywhere and fill, try and fill the whole thing.

I: Why do they try and do that?

P: Erm, I’m not sure.

I: So when you say they try to fill the whole room, do you try to do things?

P: Erm, I do. Yes.

I: So give me an example of something you might try to do?

P: I might try and learn to type on computer without looking down.

I: Okay. And so when the gas tries to fill the room, is it the same sort of thing, do we mean the same sort of thing by the word ‘try’?

P: No, I, I think I phrased that wrong, I meant that it fills the whole area, cause it can expand.

I: Okay. So it’s not, the gas does not come in and say, ‘hm, I think I’ll fill the whole room’, and try and do it.

P: No, it just does it.

I: It just does it?

P: It tries to get out of everywhere, so if you put it in the bottle, it would be trying to get out.

‘Particles’ is a word from everyday experience, generally referring to small bits of stuff, In science, we borrow the term ‘particle’ to get across the theoretical model that all material is composed of myriad tiny sub-microscopic quanta of matter. These ‘particles’ of ‘particle theory’ are not like the hard discrete grains of sugar or sand with their definite edges and surfaces, but rather fuzzy balls of fields with no clear boundaries. The particle theory is valuable in science because the familiar properties of materials can be understood in terms of the behavior, arrangements and interactions of these very different ‘particles’ (or should we call them quanticles).

Sandra (year 7, 11-12 years old) has learnt that everything contains particles, but to her particles are the small bits of materials like salt. She found it difficult to understand how these particles of which everything was made relate to the particles she is already familiar with. This became clear when she talked about dissolving.  She knew that if salt was dissolved, it could be recovered from solution by boiling off the water:

“you can like, … boil the water so it turns into gas, and then you have salt, … left there.”

However, it would not appear the same, as:

“You’d have the same, but there would just be more particles, but they’d be smaller.”

According to Sandra “Everything has particles in it” and most things would have “like thousands and thousands of particles inside it.” The grains that Sandra could see were “sort of [particles] but you’ve got more particles inside that.” However, when asked if there were two types of particles, Sandra reported that “I don’t know.”

So although Sandra had learnt about the particulate model of matter, and accepted the premise that “everything has particles in it” she was not sure if this was just a matter of scale, with these particles being very much smaller versions of the grains that were visible in a material like salt.
We should not be surprised that pupils gets confused when we chose to use a familiar word as a label for a new concept. Quanticles are very unlike familiar particles. Even in terms of scale, the very characteristic that leads to the analogy with particles.

The term ‘reaction’ is used in at least two different technical senses in school science: as one of the components of a interaction between tow bodies such that they each experience a force (‘action-reaction’), and as a chemical change which leads to a transformation of matter leading to a new substance(s).

Y7 student ‘Lomash’ reported that he had been heating materials in a Bunsen flame in his science lessons “We were burning … coal and copper and things like that, metals.”
When he heated copper “It went black…because the flame was too hot, and - it just went black , like paper.” The copper stayed black after being removed form the flame, and this was because “it’s something else, it’s a reaction.”

Lomash was using the term ‘reaction’ in the context of a chemical change – the copper had changed to ‘something else’, suggesting that he had acquired something of the technical meaning of the term as it is used in chemistry. However ‘reaction’ is used with a much more general meaning in everyday life, and on further questioning it seemed Lomash has not appreciated the special meaning given to the word in chemistry:

I: So what’s a reaction?

L: It’s like, a reaction is something that happens.

I: Okay, so if I fell off this stool, would that be a reaction?

L: Yeah.

I: And if you laughed at me falling off the stool, would that be a reaction?

L: Yeah.

I: Oh I see. So that’s just another name for something that happens is it?

L: Yeah.

Where students already have meanings for words they come across in school science, they are unlikely to readily appreciate how the word is used in a specialised, nuanced way in this particular context. Perhaps Lomash’s teacher had emphasised that in heating the copper ‘something else’ was produced making the observed change a ‘reaction’. Certainly Lomash happily accepted this was a reaction, but apparently only in his existing vague everyday sense of the term.