Examples of alternative conceptions in a popular science book:
"Why, for example, do the atoms of sodium and chlorine stick together to form a molecule of table salt? … an atom of chlorine lacks one electron in order to complete the third shell, whereas an atom of sodium has one extra electron left after the completion of its second shell. Thus there must be the tendency for the extra electron from sodium to go over into chlorine to complete the unfinished shell…the two charged atoms (or ions as they are called) will cling together forming a molecule of sodium chloride, or in plain words table salt. In the same way an atom of oxygen that lacks two electrons in its outer shell will 'kidnap' from two hydrogen atoms their single electrons thus forming a molecule of water (H2O). On the other hand, there will be no tendency to combine between the atoms of oxygen and chlorine, or between those of hydrogen and sodium, since in the first case both have the desire to take and not to give, whereas in the second case neither wants to take.
The atoms with completed electronic shells, such as those of helium, argon, neon, and xenon, are completely self-satisfied and do not need to give or take electrons; they prefer to remain gloriously lonely making the corresponding elements (so called 'rare gases') chemically inert."
George Gamow (1961) One, Two, Three…Infinity. Facts and speculations of science, Revised Edition, Dover Publications, Inc., New York.
This extract form a work by a well respected physicist reflect a number of common misconceptions.
Read about the nature of alternative conceptions
Read about some examples of science misconceptions
Read about historical scientific conceptions
The process described of an electron moving from a single sodium atom to a single chlorine atom would not happen as it is energetically nonviable. This is a common description of the formation of ionic bonds (and in the book is accompanied by a common image representing the process) but is wrong. Sodium chloride, table salt, does not contain molecules – although this is a common misconception found among learners.
Gamow describes the formation of a water molecule (using the simile, 'kidnap') as if the bond in water is also ionic (rather than basically covalent).
Read about examples of science similes
The implication is that compounds do not form of oxygen and chlorine (when Cl2O was first synthesised in 1834) nor of hydrogen and sodium (although NaH is a well-known salt, widely used as a reagent in organic chemistry).
Gamow suggests (using anthropomorphic language) that the noble gases do not form compounds, although many such compounds are now known (though helium, neon and argon do not readily form stable compounds). Also, only helium and argon actually have complete outer electronic shells – for example, argon is ten electrons short of a full outer shell.
Read examples of anthropomorphism in science
The most serious problem here is the suggestion that chemical reactions occur to allow atoms to obtain full shells. This is a widely repeated 'fairy tale', but is an empty explanation as nearly all familiar chemical reactions BEGIN (as well as end) with species (molecules, ions) that have noble gas electronic configurations.
Read about the octet framework – a common alternative conceptual framework
