Gas Chromatography (GC) Definition: Gas chromatography is a physical method of separation in which the components to be separated are distributed between two phases‚ one being a stationary bed of large surface area‚ and the other a gas that percolates through the stationary bed. When the stationary phase is a solid‚ the separation process is more precisely called gas-solid chromatography. Introduction: Gas Chromatography is a technique widely used to separate complex mixtures of substances. Compounds
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Revision Checklist for O-Level Physics 5054 Guide for Students www.XtremePapers.net REVISION CHECKLIST for O Level Physics 5054 A guide for students How to use this guide The guide describes what you need to know about your O level Physics examination. It will help you to plan your revision programme for the written examinations and will explain what the examiners are looking for in the answers you write. It can also be used to help you to revise by using the tick boxes in Section 3‚ ‘What
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Centre Number For Examiner’s Use Candidate Number Surname Other Names Examiner’s Initials Candidate Signature Question General Certificate of Secondary Education Higher Tier June 2013 Geography (Specification A) Unit 1 40301H H Physical Geography Tuesday 4 June 2013 1.30 pm to 3.00 pm Mark 1 2 3 4 5 6 7 TOTAL For this paper you must have: the colour insert (enclosed) a pencil a rubber a ruler. You may use a calculator. Time allowed 1 hour 30 minutes Instructions Use black
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In the 18th and 19th centuries scientists wrestled with identifying and describing the nature of the “stuff” that produced change. One concept that became popular for a while was that of “caloric” (what we now call heat). “Caloric was originally conceived of as a quantity that would flow from a hotter object to a cooler one that would warm up as a result. It answered the need for a way for the cause of warming to get from here to there. Not only did caloric serve as a cause for warming‚ it
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Centre Number For Examiner’s Use Candidate Number Surname Other Names Examiner’s Initials Candidate Signature Question General Certificate of Education Advanced Subsidiary Examination June 2013 Mark 1 2 3 Biology Unit 1 BIOL1 4 5 Biology and disease 6 Tuesday 21 May 2013 1.30 pm to 2.45 pm 7 8 For this paper you must have: l a ruler with millimetre measurements l a calculator. TOTAL Time allowed l 1 hour 15 minutes Instructions l l l l l l Use black ink or black ball-point
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Nassau Christian Schools History Revision Book 2010 Amerindians Theme 1 Amerindians possibly came from Asia -- from an area called Mongolia. The Amerindians are said to be descendants of the Mongoloid people. Their ancestors were nomadic hunters from East - Central Asia. They migrated into America by an ice (land) bridge covering the Bering Strait over 20‚000 years ago. Today the term Mongoloid only applies to the ESKIMOS. Amerindians are classified as a different race because of biological
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Revision Essay A lot of literature has been written about motherhood. Wordsworth is a well known English poet who mentions motherhood and female strength in several of his poems‚ including the Mad Mother‚ The Thorn‚ and The Complaint of a Forsaken Indian Woman. This leads some critics to assume that these poems reflect Wordsworth ’s view of females. Wordsworth portrays women as dependent on motherhood for happiness‚ yet he also emphasizes female strength. The poem The Mad Mother describes a woman
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Chemistry Review (mid-term) 1. Use the equation for atomic mass to answer the following questions. (http://johnheilchem10.escuelacampoalegre.wikispaces.net/file/view/average+atomic+mass+calculations+-+3.pdf) 1. Argon has three naturally occurring isotopes: argon-36‚ argon-38‚ and argon-40. Based on argon’sreported atomic mass‚ which isotope do you think is the most abundant in nature? Explain. 2. Copper is made of two isotopes. Copper-63 is 69.17% abundant and it has a mass of 62.9296 amu.
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Education Advanced Subsidiary Examination June 2011 Sociology Unit 1 Wednesday 18 May 2011 For this paper you must have: an AQA 8-page answer book. SCLY1 9.00 am to 10.00 am Time allowed 1 hour Instructions Use black ink or black ball-point pen. Write the information required on the front of your answer book. The Examining Body for this paper is AQA. The Paper Reference is SCLY1. This paper is divided into three sections. Choose one section and answer all of the questions from
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Britain in the First world war ➢ When did World war One start? August 1914 ➢ Which country did Britain enter the war for? Belgium ➢ What was the BEF? British Expeditionary Force ➢ Why did the Schlieffen Plan not work? The resistance of the Belgians‚ BEF‚ and French stopped the Germans ➢ Why was it so important for the English to secure the channel ports in November 1914? The British were able to transport troops and supplies to France through these ports ➢ What was stalemate
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