Worksheet: Covalent Structures
In this worksheet, we will practice describing common features of covalent structures and linking their material properties to their chemical structures.
Which of the following properties can generally be used to differentiate a molecular solid from a covalent network?
- AElectrical conductivity
- BMelting point
- DChemical reactivity
At room temperature and pressure, the most stable form of sulfur is the simple molecule . However, heating the material to a high temperature can produce continuous chains of sulfur atoms. Which term best describes the type of structure displayed by high-temperature sulfur?
- DSimple molecular
- EGiant covalent
In solids displaying simple molecular structures, which type of bonding is typically present?
Which feature of simple molecular covalent structures is responsible for their low melting and boiling points?
- AStrong intermolecular forces
- BInability to crystallize
- CRepulsive intermolecular forces
- DWeak intermolecular forces
- ENo intermolecular forces
Which of the following is an example of a giant covalent structure?
- BSodium chloride
- ECarbon dioxide
Which of the following is a common property of giant covalent structures?
- BHigh density
- CHigh elasticity
- DHigh melting point
For which of the following applications are diamond or silicon dioxide not the ideal substances to be used?
- AMaking glass
Silicon dioxide (silica) forms a giant covalent structure similar to diamond’s. Which of the following diagrams best represents the structure of silica?
The graph shows the melting point for four different elements. Which of the following elements is most likely to exist in bulk as a simple molecular solid?
Why do giant covalent structures have such high melting points?
- AThe electrostatic attraction between positively charged and negatively charged ions is very strong.
- BThe intermolecular forces are very strong and require a lot of energy to break.
- CThere are no free electrons to conduct thermal energy.
- DCovalent bonds are very strong and require a lot of energy to break.
- ECovalent bonds are very weak and require a lot of energy to break.
Which of the following is not a property shared between diamond and silicon dioxide?
- AInsoluble in water
- BForming a giant covalent structure
- CLow electrical conductivity
- DVery high melting point
- EEach atom being covalently bonded to four other atoms
Diamond is one of the hardest materials found on Earth. Which of the following features of diamond’s structure is responsible for its hardness?
- ADiamond forms hollow, cage-like structures.
- BDiamond forms layers of carbon atoms stacked on top of each other.
- CDiamond forms four covalent bonds, giving it a very rigid structure.
- DDiamond forms three covalent bonds, resulting in delocalized electrons.
- EDiamond forms strong electrostatic attractions between oppositely charged ions.
Which of the following giant structures does not conduct electricity?
- AMolten magnesium oxide
- DSodium chloride dissolved in water
Which of the following properties do giant covalent and giant ionic structures both share?
- AHigh melting point
- BSolubility in water
- CFormation by the electrostatic attraction of oppositely charged ions
- DConducting electricity when molten
- ELow melting point