# Chem Pre-Lab

Good Essays
635 Words
Grammar
Plagiarism
Writing
Score
Chem Pre-Lab
Pre-Laboratory Assignment
1. What are the hazards associated with sodium hydroxide (NaOH) solution?
Sodium hydroxide solutions, especially in high concentrations, are toxic and corrosive.

2. (a) What buret reading should you record when the liquid level is as shown in Figure 2?
In Figure 2, the lower meniscus lies below the 3 mL line and 4 minor gradations that signify 0.1 values. Estimating the uncertain digit to be 0.04 mL, the reading we record for this particular buret is 3.44 mL.

(b) How will you recognize the end point of your titration?
We know that that the end point of the titration is reached when, after drop after careful drop of NaOH, the solution in the flask retains its pale pink color while swirling for about 30 seconds (as opposed to the pink color simply disappearing as the base mixes into the solution).

3. A student collected the following data in the laboratory. mass of flask, g 52.87 mass of flask and sample, g 53.42 concentration of NaOH solution, M 0.101 initial buret reading, mL 0.50 final buret reading, mL 23.78 (a) What is the mass, in grams, of the sample?
The mass of the sample is given by the mass of flask (52.87 g) subtracted from the mass of flask and sample (53.42 g). masssample = massfs – massf = (53. 42 – 52.87) g masssample = 0.5500 g

(b) What volume, in liters, of NaOH solution was used in the titration?
The volume of NaOH solution used in the titration is given by the initial buret reading subtracted (0.50 mL) from the final buret reading (23.78 mL).
VNaOH = Vf – Vi = (23.78 – 0.50) mL
VNaOH = 23.28 mL
However, since we are looking for the volume in liters, and 1 L = 1000mL:
VNaOH = (23.28 mL)(1 L/1000 mL)
VNaOH = 0. 02328 L.

(c) How many moles of NaOH solution were used in the titration?
The number of moles of NaOH solution used in the titration is given by multiplying the volume of NaOH used in the solution (0. 02328 L) with the concentration of NaOH (0.101 M). It should also be

## You May Also Find These Documents Helpful

• Powerful Essays

Hydrogen Ion Per Liter: (Mols/L of H+  25 mL = .025 L x 40 = 1L)…

• 757 Words
• 4 Pages
Powerful Essays
• Powerful Essays

The average titre (19.3mL) was used for the volume of sodium hydroxide, whilst the concentration was 0.1 molL-1. 0.00193 moles of sodium hydroxide were used in this experiment.…

• 1283 Words
• 6 Pages
Powerful Essays
• Good Essays

Step 3: Fill buret with NaOH, obtain a 50 ml buret and fill with .100M NaOH solution.…

• 496 Words
• 2 Pages
Good Essays
• Satisfactory Essays

1. To titrate a hydrochloric acid solution of unknown concentration with 0.50M sodium hydroxide, and determine the molarity of the hydrochloric acid…

• 561 Words
• 3 Pages
Satisfactory Essays
• Satisfactory Essays

9. If you went too far past the end point, please record the results of your trial. Include all sets of data in your lab report.…

• 790 Words
• 4 Pages
Satisfactory Essays
• Satisfactory Essays

3. What volume of water is needed to dilute 275.0 mL of 7.95 M AlCl3 solution to a concentration of 0.820 M?…

• 907 Words
• 5 Pages
Satisfactory Essays
• Good Essays

2. To titrate a hydrochloric acid solution of “known” concentration with standardized 0.5M sodium hydroxide.…

• 1882 Words
• 12 Pages
Good Essays
• Satisfactory Essays

Trial 3: .1010 M of NaOH = moles of NaOH / 0.0158 L = 0.0015958 mols of NaOH…

• 304 Words
• 2 Pages
Satisfactory Essays
• Powerful Essays

deionized water to make a 250 mL solution, the molarity of that solution would be 0.00935 M.…

• 1576 Words
• 7 Pages
Powerful Essays
• Good Essays

## Blah

• 1432 Words
• 6 Pages

ACID-BASE TITRATION CURVES Report Sheet Calculations 1. Titration of HCl (Standardization of NaOH) a. Determine the moles of HCl.…

• 1432 Words
• 6 Pages
Good Essays
• Satisfactory Essays

This experiment is dealing with the relative accuracy of an individual measurement. Data will be provided to perform the calculations asked for. The purpose of this experiment is to know how to use significant figures and to get formularized with making proper laboratory reports.…

• 786 Words
• 4 Pages
Satisfactory Essays
• Good Essays

An acid-base titration is carried out by adding an acidic titrant to a basic solution. At which point should the titration be stopped and the volume of titrant used be recorded?…

• 542 Words
• 3 Pages
Good Essays
• Good Essays

1) If we increase the molarity of NaOH from 0.1M to 0.2M, it will actually take less number of drops in order to change the color of the solution. This is because the more concentrated a substance is, less of the substance is needed to cause an equilibrium shift.…

• 531 Words
• 3 Pages
Good Essays
• Good Essays

To perform the titration take the pipette 20 mL of the sample solution into a 250 mL…

• 692 Words
• 3 Pages
Good Essays
• Satisfactory Essays

= 0.011897 molAmount of FA3 = Amount of FA1Concentration of FA3= Amount of FA3 / Vol of FA3 solution= 0.011987 / (250/1000)= 0.047589 mol dm-3Amount of FA3 in 20.0cm3 of FA3= 0.047589 x 20.00/1000= 0.0009518 molMole ratio of FA3:FA2 used is 1:2Amount of FA2 used= 2 x 0.0009518= 0.0019036 molConcentration of FA2=0.0019036 / (25.43/1000)= 0.074856 mol dm-3…

• 386 Words
• 2 Pages
Satisfactory Essays