Question

I need help understanding these questions. An explanation would be great.

Answer 1

Here is my graph and questions

Answer 2

LOL its tooo big u do it

Answer 3

post one question at a time, I'm not comfortable with downloading files to my computer

Answer 4

Okay, did you see the graphs though?


Complete the following calculations for each part of the lab, showing your work neatly, labeling each calculation with a subtitle, and giving a brief written explanation of each calculation.
1. Determine the volume of sodium hydroxide added to the flask from the buret.
2. Calculate the molarity of the Hydrochloric acid in the flask. You may refer to the Titration demo at the beginning of the honors lesson, just above the Virtual Lab to see sample calculations.
3. Describe the graph of pH values over the course of the reaction in Part II. Was the change in pH consistent over the course of the reaction? Do your best to explain the reason for the shape of the pH curve in your own words.
4. Why is it important to stir the solution in the flask as you add titrant from the buret?
5. If a student did not remove all of the bubbles from inside the buret before reading the initial volume and beginning the titration, will this cause the calculated concentration of the hydrochloric acid determined from that trial to be higher or lower than the actual concentration? Explain your answer in complete sentences.
6. Describe at least three possible sources of error in a titration experiment like this and, for each, explain whether the error would result in a calculated molarity that is too high or too low.

Answer 5

Here is a picture of the chart

Answer 6

what is it that you don't understand?

Answer 7

Well I do FLVS. in my chemistry lesson it made me do a virtual lab. This is the lab report that I am supposed to do. It doesn't give any explanation in the lesson or in the instructions for this lab report. I got all of the information but when it comes to those questions I don't fully understand what I am supposed to do or how to do it

Answer 8

okay, well for the first question it asks you to determine how much NaOH you added, do you know what a burette is?

Answer 9

A buret is a long, narrow piece of glassware that is used to deliver small amounts of one reactant to a flask containing the other reactant. The bottom of the buret can be adjusted, using the stopwingspan, to release a small stream of liquid or add the reactant drop by drop. This allows you to carefully add the reactant until you reach the end of the reaction

Answer 10

lol don't copy and paste, well all you have to know is that when you add liquids with a buret you do it by subtraction

so you start off with 50 mL then at the end you end up with 30 mL left in the buret, how much did you add?

Answer 11

20mL?

and sorry it took so long, I had to run and grab something

Answer 12

no problem, yep thats right can you answer number 1 now?

Answer 13

for 2, you use the formula

molarity =moles/L of solution

find how many moles of NaOH you added, these will be equal to the moles of HCl present

(this is because each molecule of NaOH releases 1 OH- and each HCl releases one H+)

then use the same formula to find the molarity of the HCl

Answer 14

so it would be

Molarity = 20/L?

Answer 15

no, they had to give you the molarity of NaOH to start with, and the 20 mL is the volume which goes underneath, you're solving for moles

Answer 16

oh okay, I am still confused though. Like I said before. My lessons didnt give me any insight on this stuff

Answer 17

lol i would then suggest that you switch schools if you they're not teaching you anything, i mean this is really basic stuff

Answer 18

yeah. I talked to my teacher and she said that she would try to fix it but it didnt work out as planned.

but about # 2, the equation would have to be ?/20L

Answer 19

nope, convert mL to L

Answer 20

so if i have 20L i would have 0.02mL?

Answer 21

your conversion is incorrect