Identifying, Synthesizing, and Reacting an Unidentified Ionic Substance

A vial containing white powder concealed in an un-labeled container delivered to a presidential candidate was sent for lab analysis. Therefore, the objective of this report is threefold. The first objective is to identify what the white powder is made of as well as establish the chemical and physical properties. Using lab tests, the second objective is to produce 2.0 grams of the chemical, and the last objective is getting 2.00 grams (Yield) of the solution. Thus, the tests conducted were summarized in the table 1 below. The tests on the white powder eventually identified it as Potassium Chloride (KCl) with the identification number 7447-40-7. 

LD50 is the abbreviation for the average dose of the chemical considered to be lethal when consumed and for KCl, the lethal dose is 3,020mg/kg. Some of the potential risks associated with the compound consist of g astrointestinal ulceration, neuromuscular symptom, and confined pain and swelling due to subcutaneous or intravenous dispensation (Mengel, 2016). The compound is also known to be beneficial and some of its uses are in the production of medicine, fertilizers, and processing of food. 

Test	Procedure	Observation	Inference
Ammonium	5mls of water was put in a test-tube followed by 1ml 6M Sodium Hydroxide	The smell of ammonia was not present	Ammonium ions absent
Flame Test	5mls of water were put in a test-tube followed by 1ml of 6M Sodium Hydroxide. Later it was placed on the flame.	The flame burned with a pale violet color.	Potassium was present.
Sulfate	1ml of 6M Hydrochloric acid was put in a test-tube followed by 1ml of Barium Chloride solution.	There was no observation of a white precipitate.	Sulfate ions are absent.
Chloride	1ml of 6M Nitric acid was put in a test-tube followed by 1ml of silver nitrate solution.	An observation of a white precipitate was made.	Presence of Chloride ions.
Nitrate	3mls of 18M Sulfuric acid was put in a test-tube followed by 2mls of Iron Sulfate.	There was no brown ring formation at the junction of the two liquids.	Nitrate ions absent.
Carbonate	1ml of the un-named solution was put in a test-tube.  6M HCl was added dropwise.	No effervescence was observed.	Carbonate ions absent.
Acetate	Two milliliters of the un-named solution were put in a test-tube.  One drop of H 2 SO 4 was put, followed by one milliliter of ethanol before being placed in a bath of water.	No observable fruity smell was made.	Acetate ions were absent.

Table 1: Tests Conducted on the White Powder 

Results 

The equation for the acid to base titration is 

KOH (aq) + HCl (aq) H2O (l) + KCl (aq) 

Calculation of the amounts of reactants 

K = 39.098 

O = 15.999 

H = 1.008 

Cl = 35.45 

Thus, 

KOH = 15.999 + 1.008 + 39.098 = 56.105 g/mol 

HCl = 35.45 + 1.008 = 36.458 g/mol 

Hence, 

Grams of HCl needed = (1.68 x 36.458) ÷ 56.105 = 1.09g 

Calculation of acid to base percentage yield 

= 100% x (1.68g ÷ 2g) = 84% 

Equation for the Precipitation titration used 

K 2 CO 3 (aq) + CaCl 2 (aq) CaCO 3 (s) + 2KCl (aq) 

Calculation of the quantity of reactants 

K = 39.098 

C = 12.011 

Ca = 40.078 

Cl = 35.45 

O 2 = 15.999 

Thus, 

K 2 CO 3 = 3(15.999) + 2(39.098) + (12.011) = 138.204 g/mol 

CaCl 2 = 2(35.45) + 40.078 = 110.978 g/mol 

Hence, 

Grams of CaCl 2 needed = (2.4 x 110.978) ÷ 138.204 

= 1.93g 

Calculation of the precipitation’s yield in percentile 

= 100% x (2.4g ÷ 2g) = 120% 

Discussion 

The experiment had some errors and the two primary sources were identified as i ncorrect computation of the molarity and the incorrect reading of the scales. Hence, the effects of the sources of error were established as follows. The incorrect computations of the molarity lead to wrong readings of the endpoint of the reaction and as such, the results were highly flawed (Hansen, Transtrum & Quinn, 2018). Similarly, the incorrect reading of the scales leads to wrong observations which affected the results obtained as they were contrary to the expected results. Verification of the products is summarized in table 2 below. 

Test	Procedure	Observation	Inference
Solubility test	Potassium was dissolved in distilled water.	It took 20-35 seconds to dissolve completely.	Potassium dissolves in water.
Solubility test	Potassium was dissolved in 1M hydrochloric acid.	No observable change was noted.	Potassium does not dissolve in HCl.
Solubility test	Potassium was dissolved in 1M Sodium Hydroxide solution.	It is dissolved to form a clear liquid.	Potassium dissolves in NaOH to form clear solutions.

Table 2: Verification of the products 

The Advantages of Acid to Base Titration are low cost related to the equipment and relative ease of performing the experiment while the disadvantages include high amount of chemical being left behind as waste. Moreover, i t is destructive as large quantities of reactants are used in the analysis (Mengel, 2016) . Similarly, precipitation has advantages too that include simplicity in using the method and availability of equipment for the reaction. However, just like the acid to base titrations, precipitation has disadvantages which comprise consumption of time when performed manually and the need for the elements to be titrated to be well researched to establish their reactivity or to avoid end point errors in the results. 

Each of the reactions was successful as indicated by the percentage of the yield with the aid to base titration having a yield of 84% while the precipitation had 120%. Furthermore, the verification tests conducted supported the results obtained from the initial tests as the results were similar as expected. Thus, the best method of reaction is the precipitation as it is much safer compared to the acid to base titration. Moreover, the yield obtained from the reaction was much higher compared to the acid to base reaction and is much easier to conduct. 

References 

Hansen, L. D., Transtrum, M. K., & Quinn, C. F. (2018). Introduction to Titration Calorimetry. In Titration Calorimetry (pp. 5-7). Springer, Cham. 

Mengel, K. (2016). Potassium. In Handbook of plant nutrition (pp. 107-136). CRC Press.