Chem 209 - Study guides, Class notes & Summaries

CHEM 209 Quiz 2 Latest Update Graded A+ Question: What is the chemical equation representing the reaction between Fe3+ and thiocyanate? - a. SCN-(aq) + Fe3+(aq) = Fe(SCN)2+(aq) - b. Fe3+(aq) + SCN-(aq) = Fe(SCN)2+(aq) - c. Fe(SCN)2+(aq) = SCN-(aq) + Fe3+(aq) - d. Fe(SCN)2+(aq) = Fe3+(aq) + SCN-(aq) - Answer: b. Fe3+(aq) + SCN-(aq) = Fe(SCN)2+(aq) Explanation: This equation shows the formation of the complex ion Fe(SCN)2+ from Fe3+ and thiocyanate ions. Question: Provide the...

Chem 209 Quiz Questions Quiz 3 Latest Update Graded A+ Question: Provide a block diagram of a GC instrument, indicating all essential components. - a. Sample Injector, Mobile Phase Reservoir, Detector, and Read-out - b. Mobile Phase, Sample Port, Detector, and Output - c. Solvent Reservoir, Injector, Moving Phase, Sensor, and Display Answer: a. Sample Injector, Mobile Phase Reservoir, Detector, and Read-out Explanation: This diagram outlines the fundamental components of a Gas ...

CHEM 209 Quiz 1 Latest Update Graded A+ Question: What is a back titration? - a. A method where excess titrant is added first and then the remaining is titrated - b. A titration where the initial solution is known and the excess is titrated carefully - c. A technique involving titration with a known excess of titrant, followed by titration of the excess - Answer: c. A technique involving titration with a known excess of titrant, followed by titration of the excess Explanation...

CHEM 209 - Chapter 6 – Homework Questions and Answers 100% Verified 1. Systemic name for Na2S2O3 (hypo): Sodium thiosulfate - Sodium thiosulfate is the Systemic name for Na2S2O3. It's used in various applications including as a photographic fixer and in medical treatments. 2. Systemic name for N2O (laughing gas): Dinitrogen monoxide - Dinitrogen monoxide is the Systemic name for N2O, commonly known as laughing gas, used in medical and dental anesthesia. 3. Systemic name fo...

CHEM 209 Quiz 3 Latest Update with Verified Solutions Provide a diagram illustrating the key components of a GC instrument. Answer: Reservoir for Mobile Phase (pressurized helium cylinder) -> Oven -> Sample Injector (micro-syringe) -> Stationary Phase (column) -> Detector (thermal conductor or flame ionization detector) -> Readout (computer) What variables are typically plotted on the x- and y- axes of (a) a chromatogram and (b) a calibration curve? a. x: time, y...

CHEM 209 Quiz 3 Latest Version with Complete Solutions What variables are typically plotted on the x- and y-axes of a chromatogram? x-axis: time, y-axis: response What variables are typically plotted on the x- and y-axes of a calibration curve? x-axis: concentration, y-axis: peak area What term describes the time it takes for a molecule to move through the column? retention time What term describes the material coating the inside of the column in chromatography? stationary...

CHEM 209: QUIZ 1 with Complete and Verified Answers 1. What is a "back titration"? Answer: It's a technique where the concentration of an analyte is determined by reacting it with an excess of a known reagent. 2. What is the balanced chemical equation for the complete reaction between CO32− and HCl? Answer: CO32−(aq) + 2H+(aq) → H2O(l) + CO2(g) 3. What is the balanced chemical equation for the complete reaction between KHP (KHC8H4O4) and NaOH? Answer: KHC8H4O4(aq...

Draw a block diagram of a GC instrument, labeling all the important components. - Mobile phase reservoir ---> Sample injector (micro syringe) ---> Stationary Phase (column) ---> Detector (thermal conductor) ----> Read-out (computer) In a GC experiment, a student injects 2.0 μL of a 20% ethanol/water solution into the GC. Calculate the weight of ethanol that has been injected. (The density of ethanol is 0.789 g/mL at 20° C.) - 0.789 g/ml -> 0.789 mg/μL 20% of 2.0 = 0.4 0....