Science Education International
By Al-Balushi, S. M., Ambusaidi, A. K., Al-Shuaili, A. H., & Taylor, N
“Omani twelfth grade students’ most common misconceptions in chemistry”
Publisher:
3/22
Pp. 221-240
2012
Omani twelfth grade students’ most common misconceptions in chemistry
Type:
Data collection method: Test
Number of subjects, range: Large — 31 or more
Grade and age of subjects: 9th-12 grade — 15-18 years
Common misconceptions related to the structure of compounds
Lithium Bromide
- The most precise representation for lithium bromide is a molecular structure in which one atom of lithium is connected to one atom of bromine.
- The bond type between bromine and lithium in lithium bromide is covalent.
- The most precise representation of lithium bromide is a linear chain of lithium bromide molecules.
Water Molecule
- When water evaporates (in a closed container), it turns into individual atoms that have no bonds between them.
Sulphur Trioxide
- Sulphur trioxide is composed of two sulfur atoms each of which is bonded to three oxygen atoms (not able to recognize the function of the coefficient in 2SO3 as a part of the equation of SO3 formation).
- Sulphur trioxide is composed of three sulphur atoms each of which is bonded to two oxygen atoms (not able to differentiate between the subscript (3) and the coefficient (2) in 2SO3 in the equation of SO3 formation).
Common misconceptions related to chemical bonding
Chemical Bonds
- When a stick is broken, the bonds at the broken area are not affected.
- When a stick is broken, then the bonds at the broken area are divided into two parts, one part of which is on each side.
- Bonds are too small to be affected when a stick is broken.
- Bonds are physical (material) links between atoms.
Covalent Bond
- There is an equal attraction of shared electrons from atoms participating in the covalent bond. This is valid for all types of covalent bonds.
- The ionization of sulphuric acid into ions in water supports the expectation that the bond type between the oxygen and sulphur atom in sulphuric acid is ionic (or hydrogen bond.)
- The type of bond between oxygen atom and sulphur atom in sulphuric acid is an ionic bond.
- Water is partially polar, because oxygen has high electronegativity and attracts the shared electrons between it and the two hydrogen atoms.
- In all covalent bonds, each atom shares the same number of electrons, so the attraction of electrons from atoms participating in the bond is equal.
- There is a hydrogen bond between the oxygen atom and the sulphur atom in H2SO4.
- Water is a non-polar compound. 25.4
Ionic Bond
- There is a covalent bond between the calcium atom and the chlorine atom in CaCl2.
- In calcium chloride, each calcium atom contributes one electron and each chlorine atom contributes seven electrons.
- Calcium is considered to be a metal which has free electrons, which bond calcium andchlorine atoms together in the calcium chloride.