HK_CH7_parts 1_2 Chemical Bonding and Molecular Structure_Instructor Final Jan 2_Use this

What is biocompatibility in the context of biomaterials?

The ability of a material to interact biologically without triggering an immune response.

What are the properties required for materials used to replace damaged tissue?

Physical properties similar to the tissue they are replacing, including strength, durability, and polarity.

How do metals tend to form cations, and why?

Metals tend to form cations because they have low ionization energies, leading to the loss of electrons.

What is electronegativity?

The attraction of an atom for the shared electrons in a covalent bond.

Describe the difference between sigma and pi bonds.

Sigma bonds are formed by end-to-end overlap of orbitals, while pi bonds are formed by side-to-side overlap.

How does hybridization reconcile observed molecular shapes with the orbital overlap model?

Hybridization involves reshaping the orbitals to match the observed bond angles and molecular shapes.

What is the octet rule?

An atom will form covalent bonds to achieve a complement of eight valence electrons.

What type of bonding occurs in ionic compounds?

Ionic bonding occurs between metals and nonmetals, involving the transfer of electrons.

What effect does losing electrons have on cation size?

Cations are smaller than their corresponding neutral atoms because losing electrons reduces electron-electron repulsion.

What is a resonance structure?

Resonance structures can be drawn when the choice of multiple bond location is arbitrary, differing only in electron position.

What does VSEPR theory stand for and its significance?

Valence Shell Electron Pair Repulsion theory predicts molecular shapes based on minimizing electron pair repulsions.

How does the presence of lone pairs affect molecular geometry?

Lone pairs occupy more space than bonding pairs, affecting the angles and shapes of molecules.

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

Electronegativity values increase from left to right across a period and from bottom to top in a group.

What bond type is characterized by an electronegativity difference greater than 2.0?

Ionic bonds are characterized by an electronegativity difference greater than 2.0.

In the context of molecular shapes, what happens to bond angles as the number of lone pairs increases?

Bond angles decrease as the number of lone pairs on the central atom increases.

What is the significance of lattice energy in ionic compounds?

Lattice energy is the energy released when ions form a crystalline solid, indicating the strength of the ionic bond.

How do you identify polar covalent bonds?

Polar covalent bonds are identified by differences in electronegativity; typically, differences less than 1.6 are polar covalent.

What defines a molecule as nonpolar?

A molecule is nonpolar when there is equal sharing of electrons between atoms, resulting in no net dipole moment.