Chem test

What do atoms typically have in terms of valence electrons?

Atoms typically have 1-8 valence electrons.

What is the octet rule in chemistry?

Atoms strive to achieve an octet (8 valence electrons) through sharing or transferring electrons.

How do ionic bonds form?

Ionic bonds form between nonmetals and metals.

What represents covalent bonds in chemical structures?

Covalent bonds are represented by lines between atoms.

What is an exception to the octet rule regarding hydrogen?

Hydrogen only needs 2 electrons (like helium).

Which elements have unusual electron requirements compared to the octet rule?

Beryllium (4), boron (6), and aluminum (6) have different requirements.

Which periods can exceed the octet rule?

Elements in period 3 and below can exceed the octet rule.

Where do extra electrons typically go in molecules with odd electrons?

The extra electron is typically placed on the more electronegative atom.

What is the first step in drawing Lewis structures?

Create a skeleton structure with single bonds.

Who is usually chosen as the central atom in Lewis structures?

The least electronegative atom is usually the central atom.

What is a characteristic of resonance structures?

Some compounds can be drawn in multiple ways (resonance structures) due to delocalized electrons.

What does the formula for formal charge look like?

Formal charge = Number of valence electrons - Number of bonds - Nonbonding electrons.

What are the best formal charge rules?

1. Fewer formal charges preferred. 2. Charges closer to zero preferred. 3. Negative charges should be on more electronegative atoms.

What type of atoms can noble gases bond with?

Noble gases can only bond with highly electronegative atoms.

In the example CO2, what calculations can be demonstrated?

CO2 demonstrates formal charge calculations.

What does F-N-F illustrate in terms of chemical structure?

F-N-F shows electron distribution and bonding.