Question

explain how you would prepare 100.0 ml of 1.0 m hcl from 12 m hcl. specify amounts, glassware and sequence. write proper sentences.

Answer 1

To prepare 100 ml of a 1.0 M HCl solution from a 12 M stock, calculate the required volume of the concentrated acid, accurately measure 8.33 ml of the stock, add it to a volumetric flask, and dilute it with distilled water to the 100 ml mark.

Step-by-step explanation:

Preparing a Diluted Solution of HCl

To prepare 100.0 ml of a 1.0 M HCl solution from a concentrated 12 M HCl stock, you must perform a dilution. Here is a step-by-step guide:

1. Calculate the volume of the concentrated HCl needed using the equation M1V1 = M2V2, where M1 is the molarity of the initial solution, V1 is the volume of the initial solution needed, M2 is the desired molarity, and V2 is the final volume of the solution. Thus, V1 = (M2 x V2) / M1 = (1.0 M x 100.0 ml) / 12 M = 8.33 ml.
2. Measure out 8.33 ml of 12 M HCl using a pipette or a syringe for accuracy and transfer it into a 250 ml volumetric flask for precision.
3. Add distilled water slowly to the flask containing the acid. As you approach the 100 ml mark, add water dropwise to ensure precision, taking care to avoid splashing or strong reactions.
4. Once the volume reaches 100 ml, stop adding water. Mix the solution by inverting the volumetric flask several 1.

It's important to do these steps in a well-ventilated area while wearing appropriate personal protective equipment including gloves and eye protection. Always add acid to water, not the other way around, to prevent exothermic reactions.