Solutions Acid-Base pH

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Solutions Acid-Base pH

• ISCI 2002

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Solutions

• (1). Homeogeneous mixture of ions or molecules
• (2). Solid, liquid or gaseous solutions
• Metal alloy, air
• (3). Parts of a solution
• Solvent vs solute

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Concentrations of Solutions

• Concentrations amount of solute present in a
  given mass or volume of solution.
• by Mass
• solute mass of solute/mass of solution x 100
• A 10 glucose solution by mass contains 10.0
  grams of glucose in 100 grams of solution. (90
  grams of water and 10 grams of glucose)

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Concentrations of Solutions

• Example 15 grams of glucose was added to 500 g
  (mL) of water. Determine the concentration of
  glucose.

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Molarity

• What is a mole? Molarity?
• Molarity moles / Liter
• Mass of an element or compound that contains 6.02
  x 1023 atoms or particles.
• 1 mole of carbon 12 grams

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Molarity - Concentration

• Molarity number of moles of solute/number of
  liters of solution
• If 39.10 grams of potassium were added to 1.0 L
  of water, what would the molarity of this
  solution be?
• If approximately 11.5 grams were added to 1.0
  liter of water, what would the molarity of this
  solution be?

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Calculating Molarity

• (1). 24 grams of carbon was mixed with 1-L of
  water. Determine the molarity of the solution.
  
• (2). 3.6 grams of HCl was added to one liter of
  water. Determine the molarity of the acid.

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Concentrations

• (1). Parts per million or ppm
• (2). 1 particle of substance for every 999,999
  other particles in that solution.
• One drop of oil in a 40 gallon water tank would
  have a ppm of 1.

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Solubility

• (1). How much solute may be dissolved in a in a
  specific amount of solvent.
• Saturated, Undersaturated and Supersaturated
• (2). Solubility Table
• Solubility of a substance at a specific
  temperature

Supersaturated Solution
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Solubility Table

• (1). Determine the amount of Potassium chloride
  that can dissolve in 100g of water at 40 degrees.
  
• (2). Potassium nitrate?
• (3). As temperature increases describe what
  happens to Cesium sulfates solubility.

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Acids

• (1). Acidus means sour
• (2). Any chemical that donates or produces
  hydrogen ions (H) in aqueous solutions.
• HCl H2O --------? Cl- H3O
• Hydronium ion hydrogen ion water
• (3). Stronger the acid the lower the pH

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Acids

• Ionization acids or any molecular compound
  separates in solution to form ions.
• Dissociation ionic compounds separates into its
  ions in solution
• Strong Acids ionize close to 100 into H ions.
  (HCl HNO3 H2SO4)
• Weak Acids ionize less than 5 into ions (Acetic
  Acid)

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Bases

• (1). Bases are bitter tasting
• (2). Characteristics
• Slippery (think soap)
• (3). Examples
• Soap baking soda drain cleaners (NaOH)
• (4). Bases accept hydrogen ions or produce OH-
  (hydroxide) ions in aqueous solutions
• NaOH ---------? Na OH-
• HCl H2O -------------? Cl- H3O (water is a
  base)

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Bases

• Strong (soluble) bases dissociate completely in
  aqueous solution (NaOH LiOH KOH)
• Weak Bases ionize slightly in aqueous solutions
  (NH3)

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Salts

• Salt contains a cation (other than H) and an
  anion (other than OH-)
• Salts are formed when acids react with bases.

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Acid-Base Reactions

• (1). When an acid is added to a base a salt and
  water is formed.
• (2). Example
• HCl NaOH ----------? _______(salt?) H2O
• HCl is added to calcium hydroxide?
• (3). Neutralization reaction

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pH

• (1). pH power of hydrogen
• (2). pH based on the concentration of hydrogen
  ions in solution.
• (3). If
• H ions OH- ions (neutral solution 7 pH)
• H gt OH- then the solution is acidic (0-6 pH)
• H lt OH- then solution is alkaline (base) (8-14
  pH)

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pH Scale