Gen Chem Chapter 8

These flashcards cover essential concepts regarding chemical bonding, emphasizing ionic and covalent bonds, the octet rule, Lewis structures, electronegativity, and organic compounds.

What is a chemical bond?

An attractive force that holds atoms together in complex substances.

What are the two classes of chemical bonds?

Covalent bonding and ionic bonding.

What is ionic bonding?

A type of bonding that occurs when electrons are transferred from one atom to another, resulting in oppositely charged ions.

What is covalent bonding?

A type of bonding that occurs in molecules when atoms share electrons.

What is the octet rule?

Atoms tend to gain or lose electrons until they have achieved an outer shell containing eight electrons.

What determines the polarity of a bond?

The difference in electronegativity between the two bonded atoms.

What is lattice energy?

The amount of potential energy of a system that decreases when one mole of solid salt is formed from its gas phase ions.

How do metals form cations?

Metals lose electrons easily due to their low ionization energies.

How do nonmetals form anions?

Nonmetals gain electrons easily due to their high electron affinities.

What is the electron configuration for ions?

Ions tend to achieve the electron configuration of the nearest noble gas.

What are formal charges?

A bookkeeping method that helps to predict stability in Lewis structures by evaluating the apparent charge on an atom.

What is a polar covalent bond?

A bond that carries partial positive and negative charges at opposite ends.

What is the relationship between electronegativity and reactivity?

Electronegativity influences a substance’s tendency to undergo redox reactions.

Why is the octet rule not followed by some elements?

Elements in higher periods can have expanded octets due to the availability of d orbitals.

What are resonance structures?

Multiple Lewis structures for the same molecule that describe the delocalization of electrons.

What is the significance of bond energy in covalent bonds?

It is the amount of energy released when the bond is formed or required to break the bond.

What is meant by electron bookkeeping?

A method of using Lewis symbols to track the number of valence electrons.

What is the general trend of electronegativity on the periodic table?

Electronegativity increases from left to right across a period and decreases down a group.

How do you determine the best Lewis structure?

By evaluating which structure has the smallest formal charges and maintains proper octets.

What are organic compounds?

Compounds primarily made of carbon atoms, along with other atoms such as hydrogen, oxygen, and nitrogen.

What is the difference between alkanes, alkenes, and alkynes?

Alkanes contain only single bonds, alkenes contain at least one double bond, and alkynes contain at least one triple bond.

What are functional groups in organic chemistry?

Specific groups of atoms that confer characteristic properties to organic compounds.

What is a dipole moment?

A quantitative measure of the extent to which a bond is polarized.

What is the significance of coordinate covalent bonds?

These are bonds where one atom provides both electrons for bonding, demonstrating versatility in nitrogen chemistry.

What is the primary driving force for the formation of ionic compounds?

The attraction between positively and negatively charged ions.

What is a common characteristic of Lewis structures for diatomic gases?

They often show a shared pair of electrons, indicated by a line or dash to denote a bond.

How are lone pairs represented in Lewis structures?

As pairs of dots remaining after bonding electrons are accounted for.

Why is the stability of noble gas electron configuration significant for ion formation?

Atoms seek to achieve the stable, low-energy configuration of noble gases.

What defines a coordinate covalent bond?

A bond formed when both electrons in a shared pair come from the same atom.

What do electronegativity differences indicate about bond types?

Differences > 1.7 suggest primarily ionic character, while differences < 0.5 indicate covalent character.

What does Hess’s Law state about energy in bond formation?

The total energy change in a reaction is the sum of all changes along the path from reactants to products.

What impact does bond length have on bond strength?

Typically, shorter bonds are stronger due to the increased electrostatic attraction between nuclei and shared electrons.

How do you calculate bond energy?

It is the energy required to break one mole of bonds in gaseous molecules.

What does a resonance hybrid represent?

The actual structure of a molecule that is a conceptual mix of all valid resonance structures.

How do variations in bond angle occur in hybridized atoms?

Different hybridization states (sp, sp2, sp3) lead to distinctive bond angles.

What are examples of common organic functional groups?

Alcohols, ketones, aldehydes, and carboxylic acids.

What role do lone pairs play in Lewis structures?

They are not involved in bonding but influence molecular shape and reactivity.

What characterizes a polar molecule?

A molecule that has a net dipole moment due to unequal distribution of electrons.

What is true about the boiling points of ionic versus covalent compounds?

Ionic compounds typically have higher boiling points than covalent compounds due to stronger intermolecular forces.

What is a difference between primary, secondary, and tertiary amines?

They differ based on the number of alkyl groups attached to the nitrogen atom.

Why can some compounds break the octet rule?

Elements in period 3 and beyond can utilize d orbitals allowing for up to 18 electrons.