Chemical Bonding

What is an ion?
1. An atom or group of atoms that have gained or lost electrons.
2. An atom that shares electrons with another atom.
3. An atom or group of atoms that have gained or lost protons.
4. An atom that has more neutrons than protons.
The force of attraction between oppositely charged ions is called
1. an ionic bond.
2. a covalent bond.
3. a magnetic force.
4. weight.
Which one of the following is a property of ionic substances?
1. They have high melting points and boiling points.
2. They are all liquids at room temperature.
3. They are quite unreactive.
4. They are usually soft solids.
What is the reason for ionic compounds having high melting and boiling points?
1. The bonds between the ions are strong.
2. The bonds between the atoms are strong.
3. A small amount of energy is needed to break the bonds between the ions.
4. Ionic compounds consist of a giant crystalline structure.
Oxygen has six electrons in its outer shell and needs two more to have a full outer shell. Carbon has four electrons in its outer shell and needs four more electrons to fill its outer shell.
How many atoms of oxygen will combine with one carbon atom so that each has a full outer shell of electrons?
1. Two oxygen atoms
2. One oxygen atom
3. Three oxygen atoms
4. Neither of the other answers is correct
Which of the following elements tends to lose electrons the easiest when bonding?
1. Elements in the first two groups of the Periodic Table
2. The noble gases
3. The transition metals
4. Group IV (4) elements
What is the charge on the calcium ion in calcium oxide (CaO)?
1. +2
2. +1
3. -1
4. -2
How does a calcium ion of charge +2 become neutral?
1. By gaining two electrons
2. By gaining one electron
3. By losing one electron
4. By losing two electrons
Which one of the following statements is incorrect?
1. Group VI elements need six electrons to get a full outer shell.
2. Aluminium loses three electrons from its outer shell to from an ion of charge +3.
3. Group VII (7) elements need one electron to get a stable outer shell.
4. Group I elements lose one electron from their outer shell to form ions of charge +1.
In ionic compounds, oxygen gains two electrons.
Which one of the following is the electron structure for the oxide ion?
1. 2,8
2. 2,5
3. 2,6
4. 2,4
Bromine usually gains an electron when forming an ion.
Which of the following equations is correct?
1. Br + e^- → Br^-
2. Br → Br⁺ + e^-
3. Br → Br^- + e^-
4. Br⁺ + e^- → Br
Which of the following is the correct formula for the hydrogen carbonate radical?
1. HCO₃^-
2. NO₃^-
3. CO₃^2-
4. SO₄^2-
What is meant by a covalent bond?
1. The sharing of electrons between atoms.
2. The transfer of electrons between two atoms.
3. The attraction between two oppositely charged ions.
4. The sharing of protons between atoms.
Which one of the following properties does not belong to a covalent substance?
1. High melting point and a brittle solid.
2. Liquid with a low boiling point.
3. Soft solid and a very poor conductor of electricity.
4. Insoluble in water and does not conduct electricity.
When a covalent bond is formed, what happens to the outer shell of electrons?
1. An electron from each atom is shared.
2. One of the atoms gains electrons while the other atom loses electrons.
3. Each atom gains electrons to reach a full outer shell.
4. An electron is removed from each atom's outer shell.
Of the following molecules listed below, which of them contains a triple covalent bond?
1. N₂
2. O₂
3. H₂
4. NH₃
Which of the following pairs of elements will combine to produce a covalent bond?
1. Hydrogen and chlorine
2. Magnesium and oxygen
3. Sodium and chlorine
4. Lithium and bromine
The number of electrons gained, lost or shared by an atom in a chemical bond is also known as
1. its valency.
2. its atomic number.
3. its mass number.
4. its charge.
The valency of an element depends upon
1. the group number to which that element belongs.
2. the numbers of neutrons in its nucleus.
3. the number of protons in an atom of that element.
4. the number of the period to which that element belongs.
What is the valency of copper in copper oxide, CuO?
1. +2
2. -1
3. +1
4. -2
What do you call an atom that has gained or lost an electron?
1. An ion
2. A proton
3. A nucleus
4. A bond
Which one of the following is not a property of an ionic substance?
1. They are usually soft solids.
2. They conduct electricity when molten or dissolved in water.
3. They have high melting points.
4. They usually form crystal lattices.
Why can ionic substances conduct electricity when in solution or molten, but not when they are in the solid state?
1. When in solution or molten, the ions are free to move but not free to move in the solid state.
2. When in solution or molten, the protons are free to move, but not free to move in the solid state.
3. Electrons cannot travel through solids.
4. When in solution or molten, the atoms are free to move, but not free to move in the solid state.
Which of the following compounds is most likely to be formed when a metal reacts with a non-metal?
1. Ionic compound
2. Metallic compound
3. A gaseous compound
4. Covalent compound
Which of the following statements is incorrect?
1. Ions contain the same number of protons as electrons.
2. Ionic compounds conduct electricity.
3. An ionic bond results from the attraction between opposite charged ions.
4. Elements in group VI (6) of the Periodic Table have a valency of 2.
What is the name of the compound formed when sulfur combines with magnesium?
1. Magnesium sulfide
2. Sulfur magnesium
3. Magnesium sulfate
4. Magnesium sulfur
Which one of the the following occurs when sodium forms an ionic bond?
1. Na → Na⁺ + e^-
2. Na → Na^- + e^-
3. Na^- → Na + e^-
4. Na⁺ → Na + e^-
How does a chloride ion of charge -1 become neutral?
1. By losing one electron
2. By gaining two electrons
3. By gaining one electron
4. By losing two electrons
Which of the following is the correct electron-dot structure for the hydrogen chloride molecule?
The sodium ion has a positive charge.
Which one of the following is the electron structure of the sodium ion?
1. 2,8,1
2. 2,8
3. 2,8,2
4. 2,8,8,2
A group of atoms carrying an electric charge is known as
1. a radical.
2. a simple ion.
3. a covalent bond.
4. a crystal lattice.
Which one of the following radicals is written with the incorrect formula?
1. OH⁺
2. CO₃^2-
3. SO₄^2-
4. NO₃^-
A covalent bond is
1. a bond consisting of shared pairs of electrons.
2. a force of attraction between oppositely charged ions.
3. a force of attraction between electrons and protons.
4. a bond between negative electrons and a positive ion.
In covalent compounds, electrons are ................., while in ionic compounds, electrons are .................... What two words are missing?
1. Shared and transferred respectively
2. Shared and gained respectively
3. Transferred and shared respectively
4. Gained and lost respectively
Which of the following substances is not a covalent compound?
1. NaCl
2. O₂
3. H₂
4. HCl
How many electrons are shared in a double covalent bond?
1. 4
2. 2
3. 1
4. 6
The valency of an element is
1. the number of electrons an atom of that element must gain, lose or share in order to obtain a full outer shell.
2. the charge on an ion of that element.
3. the number of protons an atom of that element must gain, lose or share in order to obtain a full outer shell.
4. the number of the group to which that element belongs.
Which of the following elements does not have a valency of 3?
1. Sulfur
2. Aluminium
3. Boron
4. Nitrogen
What is the valency of iron (Fe) in iron sulfate (FeSO₄)?
1. 2
2. 1
3. 3
4. -2
The valencies of certain elements in the Periodic Table can vary. What is this group of elements called?
1. Transition metals
2. Noble gases
3. Halogens
4. Alkaline earth metals

Chemical Bonding

Multiple Choice Quiz