Red-Ox Reaction 2: Zinc with Hydrochloric Acid

In a small test tube and a small amount of zinc metal to 3 M hydrochloric acid.

Zinc is typically found in the +2 oxidation state in ionic compounds.

Record your observations.

Write the reduction half-reaction, oxidation half-reaction, overall

balanced chemical reaction, and net ionic equation that occurs and

identify all the oxidation states of the atoms.

Red-Ox Reaction 3: Zinc with Copper(II) Chloride Solution

In a small test tube add a small amount of zinc metal to the copper(II) chloride

solution.

Record your observations.

Write the reduction half-reaction, oxidation half-reaction, overall

balanced chemical reaction, and net ionic equation that occurs and

identify all of the oxidation states of the atoms.

Acid-Base Reactions: Movement of H⁺

Bronstead-Lowry Acid-Base reactions involve the transfer of hydrogen ions (H⁺)

from one chemical species to another. We can often determine if a liquid is acidic

or basic by seeing if it performs an acid-base reaction with an indicator.

Testing with Litmus Papers and Phenolphthalein

Litmus and phenolphthalein are two different compounds that change color

depending on whether hydrogen ions (H⁺) are added or removed from them.

Litmus turns red when an H⁺ is added to it and turns blue when an H⁺ is removed

from it. We can classify solutions as basic if they remove a hydrogen ion from

litmus and acidic if they add a hydrogen ion to litmus.

Most litmus paper is sold in two types (Red and Blue). Red litmus paper will turn

blue if a solution is placed on it that is basic. Blue litmus paper will turn red if a

solution that is acidic is placed on it.When testing with litmus paper, it is

important to dip a stir rod into the solution and then touch the stir rod to the

litmus paper. This keeps the liquid free from contamination and allows for

multiple tests with a single piece of litmus paper.

Phenolphthalein is often used as an indicator in acid-base reactions.

Phenolphthalein is colorless when the solution is acidic, but when the solution is

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