Question

You are provided with a stock solution with a concentration of 1.0x10-5 M. You will be using this to make two standard solutions via serial dilution. 1. Perform calculations to determine the volume of the 1.0x10-5 M stock solution needed to prepare 10.0 mL of a 2.0x10-6 M solution. Perform calculations to determine the volume of the 2.0x10-6 M solution needed to prepare 10.0 mL of a 5.0x10-7 M solution. You are welcome to do the calculations in your notebook prior to lab. 2. Prepare 10.0 mL of a 2.0x10-6 M solution using a graduated cylinder. Transfer the solution to a clean 50 mL beaker. 3. Prepare 10.0 mL of a 5.0x10-7 M solution using a graduated cylinder. Transfer the solution to a clean 50 mL beaker.

Answer 1

Answer:

1. V₁ = 2.0 mL

2. V₁ = 2.5 mL

Explanation:

You are provided with a stock solution with a concentration of 1.0 × 10⁻⁵ M. You will be using this to make two standard solutions via serial dilution.

To calculate the volume required (V₁) in each dilution we will use the dilution rule.

C₁ . V₁ = C₂ . V₂

where,

C are the concentrations

V are the volumes

1 refers to the initial state

2 refers to the final state

1. Perform calculations to determine the volume of the 1.0 × 10⁻⁵ M stock solution needed to prepare 10.0 mL of a 2.0 × 10⁻⁶ M solution.

C₁ . V₁ = C₂ . V₂

(1.0 × 10⁻⁵ M) . V₁ = (2.0 × 10⁻⁶ M) . 10.0 mL

V₁ = 2.0 mL

2. Perform calculations to determine the volume of the 2.0 × 10⁻⁶ M solution needed to prepare 10.0 mL of a 5.0 × 10⁻⁷ M solution.

C₁ . V₁ = C₂ . V₂

(2.0 × 10⁻⁶ M) . V₁ = (5.0 × 10⁻⁷ M) . 10.0 mL

V₁ = 2.5 mL