Unit 4 Chemistry

chem.is.try. I do nawt want to try bruh

Chemical Bond

a mutual electrical attraction between the nuclei and valence electrons of different atoms that binds the atoms together.

Polar Covalent Bonds

uneven distribution of electrical charge

Nonpolar Covalent Bonds

even distribution of electrical charge.

Bond Energy

energy required to break a chemical bond.

Dipole-Dipole forces

• found between polar molecules

• short-range forces

• very high boiling points

Hydrogen Bonds

form between hydrogen and a high electronegativity element.

London Dispersion

• results from constant motion of electrons

• creates an instantaneous dipole

• force increases as size of compound increases

Lewis Structures

dots

VSEPR(Valence-Shell electron pair repulsion)

orientated as far apart as possible.

Chemical Formula

indicates what elements are in a compound and in what proportions

Molecule

a neutral group of atoms, nonmetals, held together by covalent bonds.

Molecular formula

same as chem., but only molecules(what this means idk and idgaf)

Percent Composition Steps

1.) Determine the compound

2.) Calculate how much of each element is in the compound

3.) Use the formula part(each element)/whole(total of elements) x100. And do this for each element.

Note: Always use 3 sigfigs when using percent.

Empirical formula steps

1.) write the % or amount of element that’s given

2.) convert elements from grams to moles

3.) divide the number you get in step 2 by the lowest numbers you get in step 2. Those numbers are ur subscripts.

Molecular Formula Steps

1.) Do the empirical formula

2.) Divide the given molecular weight by total atomic mass you calculated after the empirical formula.

3.) Multiply subscripts by the answer you get

BOOM YOUR ANSWER