Title: Molarity Vit C

CHEM 104 LAB 4

Notebook

Experiment #: 4

Title: Molarity Vit C

Purpose: To understand solutions and concentrations, as well as determine Molarity and mg/ml of Vit C through titrations.

Procedure:

Titration #1: Use a known amount of Vit C from commercial source of Iodine(I2) to determine

concentration of I2

• Weight out approximately 0.5g of Vit C standard into volumetric flask.
• Dilute with water to 250 ml.
• Take 10 ml sample of Vit C solution and add 2 to 3 drops of acetic acid (source of

H+ to help solidify solution) and starch (for color indication)

• Titrate with I2
• Record ml of I2 required to reach endpoint.

Titration #2: Use predetermined concentration of I2 to determine Molarity and mg/ml of Vit C in orange juice

• Add 20 ml of orange juice to flask and dilute with water to 50 ml
• Take 10 ml of orange juice solution and add 2 to 3 drops of acetic acid (source of H+

to help solidify solution) and starch (for color indication)

• Titrate with I2
• Record ml of I2 required to reach endpoint.

Titration #3: Use predetermined concentration of I2 to determine Molarity and mg/ml of Vit C in lemon juice

• Add 20 ml of lemon juice to flask and dilute with water to 50 ml
• Take 10 ml of lemon juice solution and add 2 to 3 drops of acetic acid (source of H+

to help solidify solution) and starch (for color indication)

• Titrate with I2
• Record ml of I2 required to reach endpoint.

Titration #3: Use predetermined concentration of I2 to determine Molarity and mg/ml of Vit C in lime juice

• Add 20 ml of lime juice to flask and dilute with water to 50 ml
• Take 10 ml of lime juice solution and add 2 to 3 drops of acetic acid (source of H+

to help solidify solution) and starch (for color indication)

• Titrate with I2
• Record ml of I2 required to reach endpoint.

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