Solutions, Acids, Bases Study Guide
Vocabulary & Topics
Solution – solute, solvent
Base – strong, weak
Polar molecule
Indicator, universal indicator
Dissociation
Hydronium ions – H3O+
Concentration – concentrated, dilute
Hydroxide ions – OHSolubility – unsaturated, saturated,
Ph – 1-14 (7 is neutral)
supersaturated
Neutralization
Alloy
Salts – ionic compounds formed from
Acid – Strong, weak
neutralization of acids and bases.
Practice Questions – Answers on the website
What are three factors that affect rate of dissolution?
Solute size – decreasing the size of the individual particles or grains of solute can
increase surface area. Increased surface area exposes more solute to the solvent,
speeding up the dissolution.
Temperature – increased temperature speeds up the molecules of the solvent, allowing
more solvent to come into contact with the solute.
Stirring or mixing – mechanically mixing the solvent and solute allows more solvent to
come into contact with the solute.
What is created when an acid is combined with a base?
An acid and a base can be combined in what is known as a neutralization reaction. In
this reaction, the pH will become something between the pH’s of the acid and the base.
When they are combined, the products are water (from the H+ and OH- ions) and an
ionic compound known as a salt.
Name 3 characteristics that acids and bases share.
Acids and bases can both be
corrosive
poisonous
electrolytes (can conduct electricity)
Both can also be described as having unique tastes and capable of changing the color of
indicators.
Describe the process of dissociation of phosphoric acid (H3PO4).
During the dissociation of acid, the solute (H3PO4) is dissolved in water. The polar
(having slightly positive and negative ends) water molecules surround the solute. The
slightly negative ends of the water molecules are attracted to the positive ends of the
compounds (H+). The slightly positive ends of the water molecules are attracted to the
negative ends of the compounds (PO4). The compound is then pulled apart. Free H+
ions then bond with other water molecules to form hydronium ions (H3O+).
Describe the difference between a weak base and a strong base.
Strength of a base results from the degree or amount of dissociation that occurs when
the substance is dissolved in water. A strong base will dissociate almost completely
(break apart into component ions). A weak base dissociate but not nearly as completely
as a strong base. The greater the dissociation, the stronger the base and the higher the
pH. Drain cleaner is a strong base while baking soda is a weak base.
What is the difference between strength and concentration of an acid?
Strength of an acid depends on the dissociation of the acid compounds (see above
question). Concentration of an acid depends on the ratio between the solute (acidic
compound) and the solvent (water). The greater the amount of solute, the higher the
concentration. Molarity is the measure of concentration of acids and bases.
How can you use a solubility curve to tell if a solution is saturated, dilute, or
supersaturated?
Most compounds have different solubility rates depending on the temperature of the
solvent. As the temperature increases, the solubility usually does too. A solubility curve
shows this relationship on a graph with amount of solute on the y axis and the
temperature on the x axis. To use the curve, find the temperature of the solvent on the x
axis. If the amount of solute is below the solubility curve for that substance, it is
unsaturated or dilute. If it is on the line, it is saturated. If the amount of solute is above
the solubility curve, the solution is supersaturated.
Describe 3 different combinations of states of matter that can be combined into a
solution and give an example of each. Example: solid dissolved in liquid (sugar water).
Liquid in liquid – food coloring in water.
Gas in liquid – carbonated water.
Solid in solid – alloy
Liquid in solid – dental amalgam
Solid in gas – ash cloud after volcanic eruption
What is formed when active metals are combined to acids? What happens when bases
are exposed to metals?
When acids are combined with active metals, like in the zinc-acid lab, the active metal
bonds with the negative ion of the acidic compound. The hydrogen is then released as a
gas. When bases are exposed to metals, nothing happens.