Solutions, Acids, and Bases

Solution

Solution

a homogeneous mixture of two or more substances in one state of matter

Solute

the substance that is dissolved

Solvent

the substance that does the dissolving (most abundant)

Solvent + solute

solution

Aqueous solution

any solution where water is the solvent

Molarity

the number of moles of solute dissolved in every liter of solution

Formula for molarity

M = moles of solute over liters of solution

Molality

the moles of solute dissolved in each kilogram of solvent

Formula for molality

m = moles of solute over kg of solvent

Formula for solubility

n (solute) = MV

Why do things dissolve

When the solvent particles are strongly attracted to the solute particles. Every solute particle is pulled away from the other solute particles and ends up surrounded by solvent particles, resulting in a homogenous mixture

Saturated solution

When a solution reaches the point where it can't dissolve any more solute

Solubility

a measure of the amount of solute that can be dissolved in a solvent under given conditions

Acid

a substance that can donate H+ ions in solution

Base

a substance that can accept H+ ions in solution

Conjugate base

an acid loses a H+

Conjugate acid

a base gains a H+

Indicators

chemicals that change color depending on the pH of the solution

pH

a measure of the strength of an acid or base, a measure of the concentration of hydrogen ions in a solution.

Weak acids

acids that do not completely dissociate in water

Strong acids

less than 100% of the molecules form ions in water

Strong bases

substances that have a strong attraction for H+ in solution

Weak bases

substances that have a weak attraction for H+ in solution

Neutralization reaction

when an acid and a base react in the proper amounts to neutralize each other.

Titration

a carefully controlled reaction where an unknown solution is reacted with a known solution

Standard solution

A solution with a known concentration

Formula for calculating pH

pH=-log[H+]

Formula for neutralization reaction

MaVa = MbVb

What makes a strong acid

100% dissociation, more H+, lower pH, weak bonds with hydrogen

What makes a weak acid

less than 100% dissociation, fewer H+, higher pH, stronger bond

Example of strong acid

HCl --> H+ + Cl-

Example of weak acid

HC2H3O2 <--\> H+ + C2H3O2

Supersaturated solution

solutions that contain more solute than the solvent would normally dissolve under current conditions

Equivalence point

the point when the standard solution completely neutralizes the unknown solution because the moles of acid are equal until the moles of base