Question

i reallu need some help on chemistry if someone could help me asap that would be great !!!

Answer 1

why dont you post your question?

Answer 2

its a lab from flvs so its kinda hard

Answer 3

Procedure:

Fill the fifty milliliter buret with a 0.25 molar sodium hydroxide (NaOH) solution.
Remember that the long, narrow glass tube called the buret is used to deliver accurate amounts of a solution through a small dropper at the bottom of the buret. The volume markings go from fifty milliliters at the bottom, by the dropper, to zero milliliters at the top of the buret. The initial volume of the sodium hydroxide solution should be fifty milliliters for this lab, so the surface of the solution should be at the zero milliliter mark near the top of the buret.

Sodium hydroxide is colorless in solution.

Measure out between twenty milliliters and forty milliliters of the hydrochloric acid (HCl) solution with the unknown concentration using a graduated cylinder. Pour the solution into a one hundred milliliter Erlenmeyer flask.
Hydrochloric acid is colorless in solution.

Add two drops of the acid-base indicator, phenolphthalein, to the acid in the flask.
Phenolphthalein is colorless in acidic solutions, but it turns pink when the pH gets around 7.0 or higher. This allows the person performing the titration to know when they have reached the end point of the titration, when they have added enough of the base to neutralize the acid in the flask, because they see a light pink color in the solution.

Titrate the sodium hydroxide into the hydrochloric acid until you reach the end point, when the indicator turns the solution in the flask a light shade of pink.
Complete additional trials as needed if the titration went too far past the end point. Be sure to include all sets of data in your lab report.

Answer 4

Insert a complete data table, including appropriate significant figures and units, in the space below. Be sure to include all trials that were completed in Part I. Also include any observations that you made over the course of Part I.

Answer 5

but while im doing the lab im just so confused @aaronq

Answer 6

So it's a titration. The reaction is: \(\sf HCl+NaOH\rightarrow H_2O+NaCl\)

The point is to find the concentration of HCl. You get a sample of HCl (an acid), a known volume, and add NaOH (a base) until the indicator changes colour - this tells you that you have equal amounts of acid and base in the solution.


You can use: \(\sf \large M_{acid}V_{acid}=M_{base}V_{base}\) to find the concentration (molarity) of the acid.


M=molarity, V=volume

Makes more sense?