Chapter 6: Ions: Charged Particles in Solution

• Food preservation

- Wine, cheese, bread making

Ionization is the process of forming ions.

H atom breaks away and bonds with H2O

H atom remaining in the OH group shares its electron with the O atom

H+, H3O+, OH-

Acids produce H+ or H3O+ in water-based solutions and have a positive charge

Bases produce OH- in water-based solutions and have a negative charge

• Acids/Bases separate in H2O to form ions

• Acids: proton donors

• Bases: proton acceptors

• Acids and Bases react together to produce a neutral product

• Described in terms of electrons

• Bases donate electrons

• Acids accept electrons

1) Sensory Evaluation

2) Organic Dyes

Slippery

Acids: sour
Bases: bitter

Acids: red
Bases: blue

Green vegetables turn brighter if a base is added

1) pH scale
2) Titration
3) Indicators/Organic Dyes

The degree of (H+) or (H3O+) ions present in a solution

Demonstrate the degree of acidity of a solution through colour change

• Adding an acid (known pH) to an unknown base or the opposite and observe for a colour change

When the colour changes, calculate how many acid molecules it took to neutralize the base molecule

Where neutralization occurs (acid/base molecules are equal)

Knowing the volume and concentration of a solution

Avogadro’s number of particles of any substance

moles/L

• Maintaining blood pH

- Coating aspirin (helps digestion and prevents damage to the digestive system)

Antiacids -> neutralize acids for heartburn

++ chances of contaminating substances to survive

Low pH

Caused by a toxin that affects low-acid foods with a pH above 4.6 (dealdy)

Yeast: 4.0-7.0
Mold: 2.0 to 8.5

Dehydration

Colour, flavour, texture

Acid and a base that neutralizes batters and doughs to lighten or aerate baked products

Salt base that needs an acidic ingredient to produce CO2 for leavening

Leavens when liquid is added and again when the mixture is heated

Baking soda, dry acids and a filler

Acids are added to angel food cake to increase the white color

Chocolate cakes have a deeper, darker colour and smoother flavour if the batter is more basic

Eggs become more basic in storage as CO2 escapes through the egg shell

Need fresh eggs because their thicker egg whites trap more air

Acids develop that improve juice quality, affect colour, and increase sugar content

Helps determine the ideal harvest time

Acid: red
Alkaline: bluish purple

power of Hydronium ions

Saliva: acidic
Stomach: acidic
Pancreatic juice: basic
Bile: basic
Blood: basic

Pickling, changes texture and flavour