All AP Chemistry Resources
Example Questions
Example Question #81 : Understand Basic Chemistry
Sodium will react with oxygen and form an ionic compound. Which of the following is false concerning this interaction?
The electrons are not equally shared between sodium and oxygen
In this compound, oxygen is the anion while the two sodium atoms are defined as cations
Both oxygen and the two sodiums are given stable octets by creating the ionic compound
The ionic compound has an overall neutral charge
Sodium has a higher electronegativity than oxygen, causing it to give its electron to oxygen
Sodium has a higher electronegativity than oxygen, causing it to give its electron to oxygen
Electronegativity is defined as the tendency of an atom to attract an electron in a bond that it shares with another atom. Because oxygen wants to receive two elctrons, while both sodiums wish to lose one electron, oxygen has a higher electronegativity than sodium. Typically, electronegativity can be seen as increasing as you go to the top right of the periodic table. For example, fluorine has a higher electronegativity than nitrogen.
Example Question #1 : The Periodic Table
What is the energy required to form a gaseous cation from a gaseous atom?
Free energy
Electronegativity
Kinetic energy
Ionization energy
Ionization energy
This is the correct definition of ionization energy. By removing an electron from an atom, a cation is produced.
Example Question #2 : The Periodic Table
Why can some atoms exceed the octet rule?
They have d-orbitals where the extra electrons can go
They are nonmetals
They are very electronegative.
They do not exhibit any intermolecular forces
They have d-orbitals where the extra electrons can go
Atoms in the third period and above have d-orbitals that can hold up to 10 elecrons. This is what allows for atoms to exceed the octet rule.
Example Question #111 : Ap Chemistry
What properties do metallic compounds have that others lack?
Conductivity in the liquid phase
Conductivity in the solid phase
Solid at room temperature
Brittle lattice structure
Conductivity in the solid phase
Metallic compounds have unique properties due to their electron motility. In metals, electrons are able to move freely around and between atoms. In non-metals, electrons are more tightly bound to the nucleus due to increased nuclear positive charge and decreased atomic radius. The fluidity of electrons in metals allows them to conduct electric charge.
Metals are generally non-brittle. Metals are solids at room temperature and conduct electricity in the liquid phase, but they share these properties with a number of non-metal compounds as well.
Example Question #16 : Elements And Atoms
Why are the transition metals good conductors of electricity?
Transition metals have only partially filled valence bands. Thus, the electrons can move among the d orbitals, and this electron flow allows the transition metals to be good conductors of electricity.
Example Question #17 : Elements And Atoms
Which of the following does not determine the length of an element's atomic radius?
Number of valence electrons
Effective nuclear charge that electrons experience
Number of electron shells
Number of neutrons
Number of neutrons
The number of neutorns is the only thing out of the answer choices that does not impact an element's atomic radius. Since neutrons have no charge, they do not impact the attractive forces between electrons and protons.
Example Question #6 : The Periodic Table
Which of the following atoms is least likely to have a full octet when it is part of a molecule?
Cl
C
O
B
B
B (boron) is one of the atoms known for making fewer than 4 covalent bonds, and therefore not filling its octet. C (carbon) always makes 4 bonds, while O (oxygen) and Cl (chloride) are also known for having full octets.
Example Question #1 : The Periodic Table
Which of the following elements behaves the most like calcium?
Potassium
Bromine
Scandium
Strontium
Rubidium
Strontium
Strontium is in the same group as calcium in the periodic table, which means that they both have the same number of valence electrons; they are both alkaline earth metals with two valence electrons. This is one of the most important chemical properties, as it dictates how an element will react. Like calcium, strontium will lose its two valence electrons easily to form ionic compounds.
Example Question #1 : The Periodic Table
Which of the following best explains effective nuclear charge (Zeff)?
An electrostatic attraction between valence electrons and the nucleus
The charge of an electron
The atomic mass of an element
The number of protons and neutrons of an element
The charge of any nucleon
An electrostatic attraction between valence electrons and the nucleus
The correct answer choice is an accurate explanation of effective nuclear charge. Since electrons are negatively charged, they are attracted to protons, which are positively charged. Protons are located in the nucleus of an atom.
Example Question #9 : The Periodic Table
Which of the following elements are classified as a non-metal?
Rn
W
Na
Be
Hg
Rn
Rn is radon, a noble gas, which is not a metal. As a rule, elements to the left are metals, elements to the right are non-metals. The barrier would be the elements that are immideately to the right of the transition metals