{"id":156,"date":"2012-09-06T12:54:16","date_gmt":"2012-09-06T16:54:16","guid":{"rendered":"http:\/\/web.colby.edu\/ch331public\/?page_id=156"},"modified":"2017-09-18T12:41:36","modified_gmt":"2017-09-18T16:41:36","slug":"measurement-lab-practical","status":"publish","type":"page","link":"https:\/\/web.colby.edu\/ch331public\/measurement-lab-practical\/","title":{"rendered":"Measurement Lab Practical"},"content":{"rendered":"<div title=\"Page 1\">\n<p>Making careful lab measurements is an essential skill for all chemists. This lab practical is designed to be a refresher on basic lab skills and then test your abilities to make specific solutions. Your task is to prepare about 50 ml of a Ca(II) solution with 500 ppb Ca(II) by weight with an accuracy of better than 1%. \u00a0Your grade will be based entirely on your ability to meet this concentration target.<\/p>\n<p>Below are references to specific lab apparatus and some helpful hints. Use these resources to prepare your test solution. <strong>Every aspect of this lab must be your own work<\/strong>. You may not share calculations, solutions, or procedures with other students. Your lab notebook must contain all of the details specific to your solution preparation. Do these calculations before coming to lab.<\/p>\n<p>Resources:<\/p>\n<p>Available reagents: \u00a0Solid CaCO<sub>3<\/sub>, CaCl<sub>2<\/sub>, distilled water, dilute acids and bases.<\/p>\n<p>Equipment and Instructions:<\/p>\n<ul>\n<li>Mass Measurement: Harris, section 2-3 and Mettler Manual<\/li>\n<li>Burets, Volumetric Flasks, and Pipettes: Harris, sections 2-4 to 2-6<\/li>\n<li>Drying and Calibration: Harris, sections 2-8 and 2-9.<\/li>\n<\/ul>\n<p>Hints: \u00a0Please consider the nature of the reagents. \u00a0Is the reagent a primary standard? \u00a0Is the reagent dry? \u00a0Is it soluble?\u00a0How much sample do you need? \u00a0 What are the practical limits of the equipment available to you. \u00a0We don&#8217;t need to make 500 liters of the Ca standard, but you also should plan on working with reasonable quantities of all reagents.<\/p>\n<p>Evaluation: Fill an ICP tube with your test solution and bring it to the instrument lab for analysis by ICP. \u00a0 We will analyze your samples while you wait. \u00a0You will receive full marks if you sample is 500 ppb in Ca(II) (within the analytical uncertainty of the instrument). \u00a0 If your sample fails the test you must remake the sample until you prepare the solution correctly. \u00a0 You will receive a 20% penalty for each try, so it is to your advantage to plan you work carefully.<\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Making careful lab measurements is an essential skill for all chemists. This lab practical is designed to be a refresher on basic lab skills and then test your abilities to make specific solutions. Your task is to prepare about 50 &hellip; <a href=\"https:\/\/web.colby.edu\/ch331public\/measurement-lab-practical\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":184,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"open","template":"","meta":{"ngg_post_thumbnail":0,"footnotes":""},"_links":{"self":[{"href":"https:\/\/web.colby.edu\/ch331public\/wp-json\/wp\/v2\/pages\/156"}],"collection":[{"href":"https:\/\/web.colby.edu\/ch331public\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/web.colby.edu\/ch331public\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/web.colby.edu\/ch331public\/wp-json\/wp\/v2\/users\/184"}],"replies":[{"embeddable":true,"href":"https:\/\/web.colby.edu\/ch331public\/wp-json\/wp\/v2\/comments?post=156"}],"version-history":[{"count":7,"href":"https:\/\/web.colby.edu\/ch331public\/wp-json\/wp\/v2\/pages\/156\/revisions"}],"predecessor-version":[{"id":530,"href":"https:\/\/web.colby.edu\/ch331public\/wp-json\/wp\/v2\/pages\/156\/revisions\/530"}],"wp:attachment":[{"href":"https:\/\/web.colby.edu\/ch331public\/wp-json\/wp\/v2\/media?parent=156"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}