All AP Chemistry Resources
Example Questions
Example Question #41 : Bonding And Forces
What is the character of the bonds in a molecule of ammonium?
2 polar covalent bonds, 2 ionic bonds
3 polar covalent bonds
3 polar covalent bonds, one coordinate covalent bond
4 polar covalent bonds
3 polar covalent bonds, one coordinate covalent bond
Ammonium is NH4+. It is formed by the association of NH3 with H+. Thus, NH3 acts as a Lewis base, and H+ is a Lewis acid. This is a coordinate covalent bond, and there is one of these in the molecule. The remaning three bonds are polar covalent (N–H bonds).
Example Question #1 : Types Of Chemical Bonds
What type of compound is ?
Covalent
Metallic
Ionic
Polyatomic ion
Covalent
Covalent compounds generally form between two nonmetals that will both share electrons to complete their octets. Boron (B) is a metalloid and can act as a metal or nonmetal. In its bonds with fluorine (F), however, the two compounds have relatively similar electronegativities. A lack of difference in electronegativity results in covalent bonds.
Ionic compounds form between metals and nonmetals through a transfer of electrons, Metallic compounds are built from only metals. Polyatomic ions will have a formal charge.
Example Question #2 : Types Of Chemical Bonds
What property determines the polarity of a covalent bond?
The electronegativities of the atoms involved
The atomic radii of the atoms involved
The molecular geometry
The electronic geometry of the compound
The electronegativities of the atoms involved
Polarity in a bond results from an uneven sharing of electrons. An extreme example is an ionic bond, in which an electron is almost fully transferred from one atom to another due to the second atom's electron affinity.
In order to generate an uneven pull on shared electrons, the atoms involved in the bond must have significantly differing electronegativities. This will cause one atom to pull electrons closer to its nucleus, away from the other atom involved.
Molecular and electronic geometry can affect the polarity of a compound, but do not directly affect polarity of a single given bond. Atomic radius does not play a significant role in polarity.
Example Question #1 : Types Of Chemical Bonds
What types of bonds are present in the molecule ?
Double covalent bonds
Single covalent bonds
Ionic and covalent bonds
Single and double covalent bonds
Single and double covalent bonds
In carbon has a single bond to each hydrogen and a double bond to oxygen. Carbon must form four bonds to satisfy the octet rule. Only single bonds can be formed with hydrogen, but oxygen can form double bonds. The carbon will thus form two single bonds and one double bond.
Example Question #3 : Types Of Chemical Bonds
What is the type of bond in which both electrons being shared are contributed by only one of the two atoms?
Coordinate covalent
Covalent
Ionic
Nonpolar
Coordinate covalent
The definition of a coordinate covalent bond is that one of the atoms donates both of the electrons being shared. This corresponds with the correct answer choice.
Example Question #81 : Compounds And Molecules
What type of bond is present between the atoms of carbon dioxide?
Polar covalent
Nonpolar covalent
Coordinate covalent
Ionic
Polar covalent
Carbon dioxide has a double bond between the carbon and oxygen molecules. Since there is a moderately large electronegativitiy difference between C and O, the bond can be described as polar covalent.
Though the bonds themselves are polar, the overall symmetry of the molecule means that carbon dioxide has a net zero dipole and is a nonpolar compound.
Example Question #82 : Compounds And Molecules
Which of the following describe a covalent bond?
Both metals give up an electron
The nonmetal gives up an electron
None of these
The metal accepts an electron
Electrons are being shared
Electrons are being shared
In a covalent bond, electrons are shared between two nonmetals. If there is a metal in the compound, that is called an ionic compound, not a covalent compound. Ionic bonds involve the complete transfer of an electron from one species to another.
Example Question #42 : Bonding And Forces
What type(s) of bond(s) is/are present in the following molecule?
RbCl
network covalent
ionic
network ionic
complex ionic
covalent
ionic
An ionic bond is a bond between a metal (Rb) and a nonmetal(Cl)
Example Question #2 : Types Of Chemical Bonds
What type of compound is ?
Metallic
Polyatomic ion
Ionic
Covalent
Ionic
Ionic compounds are formed between metals, which want to loose electrons, and nonmetals, which want to gain electrons. The sodium (Na) will completely transfer an electron to the chlorine (Cl), giving both atoms a complete octet without sharing electrons.
Covalent compounds generally form between two nonmetals that will both share electrons to complete their octets. Metallic compounds are built from only metals. Polyatomic ions will have a formal charge.
Example Question #3 : Types Of Chemical Bonds
Which of the following compounds is not held together by ionic bonds?
Covalent bonds are formed when two nonmetals are bonded together. This covalent bond means that the electrons are shared by the two atoms in order to satisfy each atom's octet. There is very little difference in the electronegativities of the two atoms involved in the bond, so neither atom pulls the electrons closer to its nucleus.
Ionic bonds are formed between a metal and a nonmetal. Due to the dramatic difference between the electronegativities of metals and nonmetals, the electrons are pulled tightly to the nonmetal, and away from the metal nucleus. This results in each atom having a full octet, even though the electrons are not shared.
Carbon and oxygen are both nonmetals, so we would expect only covalent bonds in carbon dioxide.