module h unit 5 (lessons 1-3) acids, bases, and solutions ... · pdf filemodule h unit 5...
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Module H Unit 5 (Lessons 1-3)
Acids, Bases, and Solutionspp. 263-305
1
Vocabulary• solution• solvent• solute• solubility• acid• base• indicator• pH scale
• dilute solution • concentrated
solution• saturated
solution • unsaturated
solution• neutralization
Solution - well-mixed mixture that contains a
solvent and a solute
Understanding Solutions
1. Solvent - substance present in largest amount; dissolves
other substances2. Solute - substance present in smallest amount; dissolved
by the solvent
Parts of a Solution
Water is the universal solvent because it can
dissolve most other solutes
*Very common solutionsEx. sugar water, soda, tea
*Life depends on water solutions: plants use nutrients dissolved in
water in soil, tree sap carries dissolved water to cells, blood, saliva, tears, reactions in cells
Solutions with Water
What is the solvent in this solution?
What is the solute?
What are the solvents and solutes in these solutions?
*A solution can be made of any combination of gases, liquids, or
solidsEx. Air - Gas + Gas
Antifreeze - Liquid + LiquidDental fillings - Solid + Liquid
Brass - Solid + Solid
Solutions without Water
Not all mixtures are solutions, but all
solutions are mixtures
A mixture containing small undissolved particles that
do not settle out
Colloids
Colloids
A mixture in which particles can be seen and easily separated by settling or
filtration
Suspensions
Unlike a solution it does not have the same properties
throughout; it contains visible particles that are
larger than the particles in solutions or colloids
Suspensions
Suspensions
Suspensions
Suspensions settle out upon standingEx. Muddy Water
Solutions Colloids Suspensions
Do not settle out
Do not settle out
Settle out upon standing
Pass unchanged
through filter paper
Pass unchanged
through filter paper
Separated by filter paper
Do not scatter light Scatter light Scatter light
Solutes lower the freezing point and raise the boiling point of the
solvent
Ex. freezing fresh water vs. salt water
Ex. car coolant and antifreeze
A measure of how much solute can dissolve in a
solvent at a given temperature
Solubility
When the amount of solute dissolved in a certain
amount of solvent differs
Solubility - Concentration
1. Dilute Solutions2. Concentrated
Solutions
Solubility - Concentration
Dilute solution - a mixture that has only a little solute dissolved in a certain amount of solvent
Solubility - Concentration
Concentrated solution - a mixture that has a lot of
solute dissolved in the solvent
Solubility - Concentration
To calculate concentration of a solution, compare the amount of solute to the amount of solution
and multiply by 100 %
Solubility - Concentration
Ex.10g/100g x 100% = 10%
Solubility - Concentration
Solubility - Concentration
Copper Nitrate Solutions
1. Saturated solution2. Unsaturated solution
Solubility - Saturation
Saturated solution - a solution in which no more solute can be dissolved
Solubility - Saturation
Solubility - SaturationUnsaturated solution - a solution in which more solute can added and
dissolved
Solubility - Saturation
Solubility - Saturation
Factors Affecting Solubility1. Pressure - higher pressure of
gas over solvent, the more gas can be dissolved
2. Solvents - “like dissolves like”3. Temperature - for most solids
solubility increases as temperature increases; however, gases are less soluble as temperature increases
Solvents Affect
Solubility
Temperature Affects Solubility
Acid - a compound with the following properties:
1. tastes sour2. corrosive to metals and carbonates3. turns blue litmus paper red
Acids
Name of Acid Use
Ascorbic Aid (Vitamin C) Nutrient in fruits for good health
Folic Acid Nutrient in leafy green vegetables
Nitric Acid & Phosphoric Acid Fertilizers
Muriatic Acid (Hydrochloric Acid) Clean bricks and mortar
Sulfuric Acid Batteries, refine petroleum, treat iron and steel
BasesBase - a compound with the
following properties:1. tastes bitter2. slippery3. turns red litmus paper blue4. neutralize acids
Name of Base Use
Calcium oxide & Calcium hydroxide Mortar & Cement
Calcium oxide Can also be added to make soil less acidic
Sodium hydroxide Drain cleaners
Ammonia Solutions Cleaners
Baking soda Carbon dioxide gas used to make breads rise
Bases
Acids and Bases in Solution
Hydrogen ions
Hydroxide ions
Indicator - used to determine if a
substance is acidic or basic; usually changes color
Indicators
Two Indicators1. Litmus Paper
2. pH Paper
Indicators
Litmus Paper as an Indicator
Based on the pH scale - range of values from 0 - 14 that is used to determine the
strength of acids and bases
pH Paper as an Indicator
What do you think “pH” represents?
pH Scale
pH Paper as an Indicator
Neutralization -a chemical reaction between
an acid and base that results in water and a salt
(and the acid is neutralized)
Types of Salts
See Fig. 22 on p. 247 in text
for names and uses of
common salts