Chapter 8 Solutions
solution
A solution is a homogenous mixture of two or more substances; it is made of two parts, the solvent and one or more solutes.
unsaturated solution
A solution that has less than the maximum amount of solute that can be dissolved is called an unsaturated solution.
What are three ways to measure the concentration of a solution?
Concentration can be expressed as percent by volume, percent by mass, and molarity.
What is the difference between dissociation and ionization?
Dissociation is a physical change, ionization is a chemical change. In dissociation, the solutes are ionic compounds. And in ionization the solutes are molecular compounds.
A solution can either become warmer or colder, why?
During the formation of a solution, energy is either released or absorbed.
What happens to energy when a solution forms?
During the formation of a solution, energy is either released or absorbed.
What factors affect the rate of dissolving?
Factors that affect the rate of dissolving include surface area, stirring, and temperature, because they increase the frequency and energy of the collisions between the particles of the solute and the solvent.
How do you calculate percent by mass?
Grams of Solute/Grams of Solution X 100
What 3 ways can a concentration of solution be reported?
Percent by volume, percent by mass, and molarity.
What increases the solubility of a gas in water?
Pressure
How are solutions with different amounts of solute described?
Solutions are described as saturated, unsaturated, or supersaturated, depending on the amount of solute in solution.
What are three processes that can occur when substances dissolve?
Substances can dissolve in water in three ways--by dissociation, dispersion, and ionization.
What must you know to form a saturated solution?
The amount of solute, solvent, and temperature.
How does the boiling point of a liquid solution compare to the boiling point of its solvent?
The boiling point of the solution will be higher than the boiling point of the solvent. For example, saltwater has a higher boiling point than water.
concentration
The concentration of a solution is the amount of solute dissolved in a specified amount of a solution.
solubility
The maximum amount of a solute that dissolves in a given amount of solvent at a constant temperature is called solubility.
dissociation
The process in which an ionic compound separates into ions as it dissolves. This process begins with an ionic compound and produces ions.
ionization
The process in which neutral molecules gain or lose electrons. This process begins with molecular compounds and produces ions.
saturated solution
A saturated solution is one that contains as much solute as the solvent can hold at a given temperature.
solute
A solute is a substance whose particles are dissolved in to the solvent, becoming a solution.
supersaturated solution
A supersaturated solution is one that contains more solute than it can normally hold at a given temperature.
Why might the temperature of water increase when a solution is formed?
As the solute dissolves in the solvent, energy is absorbed and used to separate and break apart molecules. Once a solution is formed, this energy is released, increasing the temperature of the solution.
dispersion
Breaking into small pieces that spread throughout water. This is how sugar dissolves.
How might you increase the solubility of a solid in a liquid?
Increase temperature of the solute
Why does crushing a solute increase the rate of solution?
Increased surface area affects the rate of dissolving. It reduces the particle size and increases surface area, allowing for more frequent collisions between the solute and solvent particles.
Salt + Water
Ion + Ion (dissociation)
What is the heat of solution?
It is the difference between the energy used to break attractions and the release of energy when new attractions are formed. This can either be exothermic or endothermic.
molarity
Molarity is the number of moles of a solute dissolved per liter of solution.
How do you calculate molarity?
Moles of Solute/Liters of Solution
Why does oil not dissolve in water?
Oil does not dissolve in water because oil molecules are nonpolar and water molecules are polar. Polar molecules dissolve other polar molecules, while nonpolar molecules dissolve other nonpolar molecules; "like dissolves like."
How can a solute be both dilute and saturated?
The solution is saturated if it contains just enough of the solute that the solvent can hold. For a solution to be dilute means it's less concentrated. Concentration is the amount of solute dissolved in a specific amount of solution. So if you have a solute that has a hard time dissolving (not very soluble), the solution will become saturated without becoming highly concentrated.
solvent
The substance in which the solute dissolves is called the solvent.
What factors determine the solubility of a solute?
Three factors that affect the solubility of a solute are the polarity of the solvent, temperature, and pressure.
What are some properties of a solution that differ from those of its solvent and solutes?
Three physical properties of a solution that can differ from those of its solute and solvent are conductivity, freezing point, and boiling point.
How does increasing the temperature of a solvent affect the solubility of a gas?
Unlike most solids, gases usually become less soluble as the temperature of the solvent increases.
The Three Types of Solutions
Unsaturated, saturated, and supersaturated.
How do you calculate percent by volume?
Volume of Solute/Volume of Solution X 100