Postlab 1. You are given a bottle of dry NaCI. In your own words, write a brief

Question

Postlab 1. You are given a bottle of dry NaCI. In your own words, write a brief description (1-2 paragraphs) of the procedure required to make 900 mL of a 0.5 M NaCI solution. The formula weight of NaCl is 58.4 g/mole. Write the description as if you were teaching to your classmate how to make this solution in the lab, showing the necessary calculations and including the units and correct measuring devices that they would need to make it properly from start to finislh. You are given a 2 M NaCI stock solution. In your own words, write a brief description (1-2 paragraphs) ach of the following NaCI concentrations: 0.5 M, 1.0 M, and 2. of the procedure required to make 10 mL e 1.5 M Write the description as if you were teaching to your classmate how to make these solutions in the would need to make them properly from start to finish. lab, showing the necessary calculations and including the units and correct measuring devices that they 3. Draw neatly on graph paper or use a graphing program like Excel to create a scatter plot with KMnO4 concentration as the X-axis and Asso as the Y-axis. Your goal is to create one graph with two scatter plots: one for the parallel dilutions and another for the serial dilutions. You will not graph the absorbance of the unknown dilution. Notice that some of the dilution concentrations are mM, while others are . Be sure to convert the concentrations so that all of them are mM or HM. You will also have to arrange your serial dilutions from smallest to largest concentration before entering them into the graph (the reverse order of the way you made them).

Explanation / Answer

ANSWER 1.
0.5 M NaCl solution contains 0.5 times the molecular weight of NaCl per 1000 mL of solution. As such formula weight of NaCl is 58.4 g/mole and hence a 1000 mL of such a solution would contain 58.4 * 0.5 g/mole = 29.2 g/mole.
900 mL of such a solution would contain = 29.2 g/mole * (9/10) = 26.28 grams

From the given bottle of dry NaCl, use a measuring steel spoon, and bit-by-bit, place samples of NaCl on a calibrated, balanced weighing-machine (digital scale) till the given reading is obtained.
Transfer the collected amount of NaCl into a graduated cylinder/beaker that can handle liquids up to 1 Litre.
In this graduated vessel, add the solvent (generally water) till the volume reading reaches the 900 mL mark, thus making the volume up to 900 mL.

Note: Under no circumstance should you separately measure out 900 mL of solvent and add it to the measured quantity of solute (in this case 26.28 grams of NaCl).

Related Questions

Navigate

• Browse (All)
• Browse P
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.