(aq) NH3+ + H+ + Cl- →NH4+ + Cl- NH3+ + H+ → NH4+ H+ + OH- → H2O (l) ∆H= -54.0 kJ/mol NH4++ OH- → NH3+ + H2O (l) (x-1) ∆H=-4.09 kJ/mol (x-1) -54.0+4.09=-49.9 NH3+ + H+ → NH4+ =- 49.9 kJ /mol (-49.9- -26.2)/-49.9 x 100 =47.3% Lab Questions: Pre: 1. The change in thermal content in a reaction 2. The amount of energy needed to change one gram of a substance 1 degree C 3. (50 mL)(1.02 g/mL)(4.18 J/g C)(25.3-21.4) = 830 J 4. 830J+8.20J/g C(25.3-21.4)= 860J 5. .25L(.6mol/1L)+
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Solvent/Water Trap Diagram Rodney Atwaters Halle Bair May 28‚ 2013 Chemistry 36100 Introduction The purpose of this lab was to produce benzoic acid by mixing sodium benzoate with hydrochloric acid. The Hydrochloric acid used in the experiment was a stock solution made by mixing HCl Acid and deionized water. HCl acid‚ historically called‚ muriatic acid or spirits of salt‚ hydrochloric acid is produced from sulfuric acid and common salt‚ NaCl (Princeton.edu). Since the early 1900 ’s‚ sodium
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Title: Penny Lab Experiment By -Objectives To determine how soap affects the surface tension of water. -Hypothesis In this experiment the hypothesis was that soap was going to affect the surface tension by weakening the bonds and allowing less water on the penny. -Materials * Penny * Beaker x2 (One containing soapy water the other containing pure tap) * Paper towels * Lab review sheet * Pencil * Pipette -Procedure First we picked who would drop the water onto
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Solubility‚ Crystallization and Melting Point Determination Post-Lab Discussion Guidelines: Part 2A and 2C: Draw tables (as in textbook) showing which combinations were soluble/miscible and which were insoluble/immiscible. Explain why this is so. Why are certain chemicals soluble/miscible when others are not? Part 3A: Calculate % recovery (this is not the same as % yield – see handout from the first day of lab if you’re confused)‚ and determine melting point of your product. Discuss % recovery
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System Laszlo Vass‚ Ed.D. Version 42-0025-02-01 Lab RepoRt assistant This document is not meant to be a substitute for a formal laboratory report. The Lab Report Assistant is simply a summary of the experiment’s questions‚ diagrams if needed‚ and data tables that should be addressed in a formal lab report. The intent is to facilitate students’ writing of lab reports by providing this information in an editable
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Lab 2 Physics 190 Acceleration “g” Due to Gravity – Method 2 Introduction Tonight we will measure the acceleration due to gravity again. This time however‚ we will collect more data and the analysis will be different. We will first fit the data using a second order polynomial. Recall for a mass falling from rest‚ that 1 (1.1) y a yt 2 2 Suppose a mass falls through n successively greater displacements‚ each time starting from rest. The displacements can be expressed a 2 y y t ;
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Kalle Watts Measurement Lab 9‚ 27‚ 2012 In this measurement lab we attempted to make the most precise and most accurate measurements. We used the materials and equipment that we had to make all of our measurements. We had to deal with significant figures and also‚ we had to designate each measurement with its proper unit. The objective of this lab was to use all of our equipment we had and make the most accurate measurements
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General College Chemistry LabPaq / Published by: Hands-On Labs‚ Inc. sales@HOLscience.com / www.HOLscience.com / Toll Free 866.206.0773 A Laboratory Manual of Small-Scale Experiments for the Independent Study of General College Chemistry 50-0123-CK-02 LabPaq® is a registered trademark of Hands-On Labs‚ Inc. (HOL). The LabPaq referenced in this manual is produced by Hands-On Labs‚ Inc. which holds and reserves all copyrights on the intellectual properties associated with the LabPaq’s
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Precision: Balance Lab Worksheet Before You Begin: You may either copy and paste this document into a word processing program of your choice or print this page. Procedure Access the virtual lab and complete the experiments. Data Below is the table that you will complete for the virtual lab. Either type your results into this table or print the table from the virtual lab (it must be submitted to receive full credit for this assignment.) To print from the virtual lab. Be sure the data
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Saliva Lab Since the amylase enzyme is present in saliva‚ starch digestion begins in the mouth. Salivary amylase changes the polysaccharide starch into many disaccharide molecules of maltase (a simple sugar) which are further broken down into glucose units by maltase enzyme in the As stated above‚ saliva contains the amylase enzyme which begins the breakdown of starches. The efficiency of starch digestion by amylase can be measured by how much simple sugar it produces under
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