CHEM 20A Study Guide - Midterm Guide: Atomic Radius, Wave Function, Diamagnetism

The process by which you will separate your solid mixture via extraction can be summarized in a separation scheme. A simplified framework for the separation procedure you will follow for the extraction experiment is on reverse. The whole idea of this worksheet is that, if you think about it and complete it before lab, you'll understand what you're doing in lab and it will all go much more smoothly/efficiently! Before you tackle this worksheet, read the lab procedure and: Mohrig, p. 142-149 AND Karty, Ch. 6. Any review of those concepts will be helpful. This worksheet will be very hard... make sure to talk to your lab instructor with any questions!! In this hypothetical example, assume you are separating o-toluic acid from naphthalene: 1) First, ill out the table below based on what you have learned about a compound's solubility behavior from your lecture text and the solubility tests. Note that diethyl ether is a good organic solvent that dissolves just about any covalent molecule that has carbons and hydrogens in it. 2) Based on your answers in (1), provide the complete acid-base reaction (including neat and precise electron movement arrows) for any compound (naphthalene or o-toluic acid) which would be soluble in 10% aq. NaOH.

PREPARATION WORKSHEET Date: TA: Section Answer the following questions using information obtained from lecture, the textbook, the lab manual, or other reliable sources. The responses will be collected at the beginning of Pre-Lab Recitation and checked at the start ofyour lab section for credit. Failure to complete all answers may result in exclusion from participating in the lab. 1. In chromatography a. what do the mobile and stationary phases do? b. what is the mobile phase in this experiment? c. what is the stationary phase in this experiment? 2. Why will a pencil be used to mark the paper rather than a pen or marker? 3. Why do we have to wait for the spot to dry before adding more dye to the spot?

Secure hitps:/session.masteringchemistry.com/myct/itemView?assignmentProblemiD-95099345 Post Lecture Homework Chapter 06 stering Formation Reactions K10 of 11> For which of the following reactions is Δ Hran 0qual to Δ H7 of the product(s)? You do not need to look up any values to answer this question. Check all that apply Course Ho Syllabus Scores eText Dynamic S The standard heat of formation, ΔH. is defined as the enthalpy change for the formation of one mole of substance from its constituent elements in their standard states. Thus, elements in their standard states have Δ Hr-0. Heat of formation values can be used to calculate the enthalpy change of any View Available Hint(s) C(s, graphite) + 02(8) CO2(g) BaCOs(s) Ba0(s)+Co2(8) Consider, for example, the reaction Modules Document User Setin table: Course Too SubstancekJ/moly 2N0 (g) + 02 (g) 2NO2 (g) -. Li(s) +1C12(1)→LiCl(s) with heat of formation values given by the following oCO(g)+02(g) CO2(8) Li(s) + 1 Cl2 (g) →LiCl(s) NO(g 90.2 O2(g) NO2(g)33.2 Submit Previous Answers Then the standard heat of reaction for the overal reaction is XIncorrect; One attempt remaining: Try Again Ali (reactants) [2(90.2) +0] Δ14.. ΔHt (products)-- 2(33.2) -114 kJ ▼ Part B