Download - Acids, Bases, and Solutions
Acids, Bases, and Solutions
Chapter 7
What is a Solution?
SolutionsSame properties throughoutContains a solvent and a solute
SolventDoes the Dissolving
Water = Liquid
SoluteThe stuff that is dissolved
Sugar
Kool-Aid
Solvent = Water
Solute = Sugar
Water is referred to as the “universal Solvent”
Why?
Water dissolves almost anything
ConcentrationHow much solute (dissolved stuff)
DiluteWeakNot a lot of solute (dissolved stuff)
ConcentratedStrongA lot of solute (dissolved stuff)
Measuring Concentration
Amount of SoluteAmount of Solvent
X 100
ExampleA solution contains 12 g of solute dissolved in 36 g of solution. What is its concentration?
Answer: 10%
12 g36 g = .33 x 100
.33 = 33%
ExampleWhat is the concentration of a solutions that contains 45 grams of sugar in 500 grams of solution?
Answer: 9%
45 g500 g= .09 x 100
.09 = 9%
ExampleHow much sugar is dissolved in 500 grams of a solution if the solution is 70 percent sugar by mass?
Answer: 350gX500 g 70%=
.7 (500) = x
X = 350g
SolubilityA measure of how much solute (dissolved stuff) can dissolve
Unsaturated Solution
Weak, DiluteVery little solute is added
Add more sugar it will dissolve
Saturated Solution
Perfect AmountNo more solute will dissolve
If you add more it will settle to the bottom
SupersaturatedAdd so much solute that it begins to pile up on the bottom of the container
Acids and Bases
IndicatorsCompounds that change color when it contacts an acid or a base
Properties of AcidsSour tasteReacts with metals (corrosive)
Turns litmus paper red
Properties of BasesBitter TasteSlippery FeelTurns Litmus paper Blue
AcidsProduce Hydrogen Ions (H+) in water
BasesProduce Hydroxide ions (OH-) ions in water
Strengths of Acids and Bases
The pH scale
The pH scaleRange of numbers from 1-14
Ph < 7ACIDIC H+ ions presentThe lower the number the stronger the acid (more H+ ions)
pH = 7NeutralNot acidic or basic H+ = OH- ions
pH > 7BASIC OH- ions presentThe higher the number the more basic
NeutralizationA reaction between an acid and a base
Salt and water produced
Neutralization
Check for Understanding
pH 1, pH 3 or pH 7 ?
Which contains the highest concentration of Hydrogen ions?
pH of 1
pH of 6 or pH of 3
Which is stronger?Which contains more H+ ions?
pH of 3
pH 10 or pH 14Which is a stronger base?
Which has more OH- ions?
pH of 14