{"id":266,"date":"2024-05-18T19:46:47","date_gmt":"2024-05-18T18:46:47","guid":{"rendered":"https:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/chapter\/3-differential-thermal-analysis\/"},"modified":"2024-05-20T15:45:05","modified_gmt":"2024-05-20T14:45:05","slug":"3-differential-thermal-analysis","status":"publish","type":"chapter","link":"https:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/chapter\/3-differential-thermal-analysis\/","title":{"raw":"3. Differential Thermal Analysis:","rendered":"3. Differential Thermal Analysis:"},"content":{"raw":"<div class=\"-3.-differential-thermal-analysis:\">\r\n<div class=\"textbox textbox--learning-objectives\"><header class=\"textbox__header\">\r\n<h2><strong><img src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image1-8.png\" width=\"34.6666666666667px\" height=\"34.6666666666667px\" alt=\"image\" \/> <\/strong><strong>Learning Objectives<\/strong><\/h2>\r\n<\/header>\r\n<div class=\"textbox__content\">\r\n\r\nAfter going through this Part, you should be able to:\r\n<ul>\r\n \t<li class=\"import-Normal\" style=\"text-align: justify\">Explain the principle and working of a differential thermal analyser.<\/li>\r\n \t<li class=\"import-Normal\" style=\"text-align: justify\">Draw and interpret DTA thermogram.<\/li>\r\n \t<li class=\"import-Normal\" style=\"text-align: justify\">Compare and contrast TG and DTA results.<\/li>\r\n \t<li class=\"import-Normal\" style=\"text-align: justify\">Explain the applications of DTA and simultaneous TG-DTA analysis<\/li>\r\n<\/ul>\r\n<\/div>\r\n<\/div>\r\n<p class=\"import-Normal\" style=\"text-align: justify\">When a molecule undergoes a physical or chemical transition, heat is either absorbed or liberated. Two thermal methods, DTA and DSC are particularly useful for investigating these physical and chemical changes.<\/p>\r\n&nbsp;\r\n\r\n<strong style=\"font-size: 1em\">3.1 Principle and Instrumentation:<\/strong>\r\n<p class=\"import-Normal\" style=\"text-align: justify\">In DTA, the difference in temperature between the sample and an inert reference (\u2206T) is measured as the sample and the reference are heated or cooled in a controlled manner.<\/p>\r\n<p class=\"import-Normal\" style=\"text-align: justify\">\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 <a id=\"_3znysh7\"><\/a>\u2206T = T<sub>s<\/sub> \u2013 T<sub>R <\/sub><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 36pt\">T<sub>S <\/sub>= temperature of sample<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 36pt\">T<sub>R<\/sub> = temperature of reference which is thermally stable<\/p>\r\n<p class=\"import-Normal\">Please go through the <em>Chemlibre<\/em> link to understand the principle and working of DTA.<\/p>\r\n<p class=\"import-Normal\"><img src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image2-16.png\" width=\"38px\" height=\"28.6666666666667px\" alt=\"image\" \/><a class=\"rId9\" href=\"https:\/\/chem.libretexts.org\/Bookshelves\/Analytical_Chemistry\/Instrumental_Analysis_(LibreTexts)\/31%3A_Thermal_Methods\/31.02%3A_Differential_Thermal_Analysis\">https:\/\/chem.libretexts.org\/Bookshelves\/Analytical_Chemistry\/Instrumental_Analysis_(LibreTexts)\/31%3A_Thermal_Methods\/31.02%3A_Differential_Thermal_Analysis<\/a><\/p>\r\n<p class=\"import-Normal\"><strong>Instrumentation and working:<\/strong> A typical DTA set up is shown in the figure given below.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 36pt;text-indent: 36pt\"><img src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image3-2.jpg\" width=\"223.749186351706px\" height=\"193.633280839895px\" alt=\"image\" \/><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 36pt;text-indent: 36pt\"><strong>Figure 3.1a.<\/strong> DTA set up<\/p>\r\n<p class=\"import-Normal\" style=\"text-align: justify\">In differential thermal analysis (DTA), the difference in temperature between the sample and a thermally inert reference material is measured as a function of temperature (usually the sample temperature). Any transition that the sample undergoes results in the liberation or absorption of energy by the sample with a corresponding deviation of its temperature from that of the reference. A plot of the differential temperature, \u0394T, versus the programmed temperature, T, indicates the transition temperature(s) and whether the transition is exothermic or endothermic. DTA and thermogravimetric analyses (measurement of the change in weight as a function of temperature) are often run simultaneously on a single sample.<\/p>\r\n&nbsp;\r\n\r\n<\/div>\r\n<div class=\"-3.-differential-thermal-analysis:\">\r\n\r\n<strong>3.2 DTA curve and its interpretation<\/strong>\r\n<p class=\"import-Normal\" style=\"margin-left: 36pt\"><span style=\"margin-left: 26pt\"><\/span>\u2206T = T<sub>s<\/sub> \u2013 T<sub>R <\/sub><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 36pt\">T<sub>s<\/sub>= temperature of sample<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 36pt\">T<sub>R<\/sub> = temperature of reference which is thermally stable<\/p>\r\n<p class=\"import-Normal\">A typical DTA curve is represented below<\/p>\r\n<p class=\"import-Normal\">\u00a0 \u00a0 \u00a0 \u00a0 <img src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image4-4.png\" width=\"222\" height=\"313\" alt=\"image\" class=\"\" \/><span style=\"margin-left: 26pt\"><\/span><strong>Figure 3.2a.<\/strong> DTA curve<\/p>\r\n<p class=\"import-Normal\"><strong><img src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image5-6.png\" width=\"47.3333333333333px\" height=\"47.3333333333333px\" alt=\"image\" \/><\/strong><strong>Brain Teaser:<\/strong><\/p>\r\n<p class=\"import-Normal\">Can you suggest why we adopt \u2206T &gt; 0 for exothermic and \u2206T &lt; 0 for endothermic transition?<\/p>\r\n<p class=\"import-Normal\"><img src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image6-5.png\" width=\"32.6666666666667px\" height=\"32.6666666666667px\" alt=\"image\" \/><strong>Activity 3A: <\/strong>The following figure represents thermal investigation. Fill in the blanks by choosing the correct option. (<span style=\"color: #ff6600\">James &amp; Tonge, 2008<\/span>)<\/p>\r\n<p class=\"import-Normal\"><span style=\"margin-left: 26pt\"><\/span><span style=\"margin-left: 26pt\"><\/span><img src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image7-3.png\" width=\"286.666666666667px\" height=\"134.666666666667px\" alt=\"image\" \/><\/p>\r\n<p class=\"import-Normal\" style=\"text-align: justify;margin-left: 36pt\">The record shown is that of a_________________ experiment since the_________ plot \u2206T which is a ______________temperature. The ___________direction of the peak indicates that a __________________reaction has occurred. This in turn implies that the corresponding _________________ change \u2206H must have been ____________ ie the value of enthalpy ________________the thermal effect was ____________ than its value _____________.This means that the sample ____________ heat during the reaction. Furthermore, there is evidence of a change _______________in the temperature is increased beyond the thermal transition. This is shown by the ___________of the just beyond the end.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 36pt\"><strong>Answers: Select from the following list<\/strong><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 36pt\">[upward\/downward, free energy\/heat capacity, greater\/less, DTG\/DTA, base-line\/background, derivative\/differential, took in\/gave out, negative\/positive, enthalpy\/entropy, before\/after\/during, exothermic\/endothermic\/isothermal, abscissa\/ordinate, distortion\/displacement.]<\/p>\r\n<p class=\"import-Normal\"><img src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image6-6.png\" width=\"32.6666666666667px\" height=\"32.6666666666667px\" alt=\"image\" \/><strong>Activity 3B: <\/strong>(<span style=\"color: #ff6600\">James &amp; Tonge, 2008<\/span>)<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 36pt\">During the Falklands campaign in 1982 many naval personnel suffered serious<\/p>\r\n<p class=\"import-Normal\" style=\"text-indent: 36pt\">burns. In 1985 the Admiralty decreed that all men on active service in Navy<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 36pt\">should be issued cotton uniforms instead of polyester ones which had been<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 36pt\">issued in 1982. Does the thermal data suggest a reason for the decision?<\/p>\r\n<p class=\"import-Normal\" style=\"text-align: justify\">\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Justify your answer?<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 36pt\"><img src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image8-4.png\" width=\"309.46750656168px\" height=\"189.436220472441px\" alt=\"image\" \/><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 36pt\"><strong> Fig.\u00a0 <\/strong>DTA curves for cotton and polyester -50 mg heated in pure nitrogen at 5\u1d52C min-<sup>1<\/sup><\/p>\r\n&nbsp;\r\n\r\n<\/div>\r\n<div class=\"-3.-differential-thermal-analysis:\">\r\n\r\n<strong>3.3 Comparison with TGA<\/strong>\r\n<table style=\"width: 431.85pt;height: 342px\">\r\n<tbody>\r\n<tr class=\"a-R\" style=\"height: 19.7pt\">\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 30px;width: 8.02083px\">\r\n<p class=\"import-Normal\"><strong>\u00a0<\/strong><\/p>\r\n<\/td>\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 30px;width: 219.312px\">\r\n<p class=\"import-Normal\"><strong>TGA<\/strong><\/p>\r\n<\/td>\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 30px;width: 305.125px\">\r\n<p class=\"import-Normal\"><strong>DTA<\/strong><\/p>\r\n<\/td>\r\n<\/tr>\r\n<tr class=\"a-R\" style=\"height: 61.85pt\">\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 80px;width: 8.02083px\">\r\n<p class=\"import-Normal\">1<\/p>\r\n<\/td>\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 80px;width: 219.312px\">\r\n<p class=\"import-Normal\">It measures change (loss or gain) in weight as the sample is subjected to controlled heating program<\/p>\r\n<\/td>\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 80px;width: 305.125px\">\r\n<p class=\"import-Normal\">It is a technique in which the difference in temperature between the sample and an inert reference material, is measured as a function of temperature<\/p>\r\n<\/td>\r\n<\/tr>\r\n<tr class=\"a-R\" style=\"height: 47.8pt\">\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 77px;width: 8.02083px\">\r\n<p class=\"import-Normal\">2<\/p>\r\n<\/td>\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 77px;width: 219.312px\">\r\n<p class=\"import-Normal\">It will detect only those physical and chemical transitions which are accompanied by change in weight.<\/p>\r\n<\/td>\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 77px;width: 305.125px\">\r\n<p class=\"import-Normal\">It can detect all physical and chemical transitions.<\/p>\r\n<\/td>\r\n<\/tr>\r\n<tr class=\"a-R\" style=\"height: 41.45pt\">\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 52px;width: 8.02083px\">\r\n<p class=\"import-Normal\">3<\/p>\r\n<\/td>\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 52px;width: 219.312px\">\r\n<p class=\"import-Normal\">This does not require an inert reference.<\/p>\r\n<\/td>\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 52px;width: 305.125px\">\r\n<p class=\"import-Normal\">This requires an inert reference material.<\/p>\r\n<\/td>\r\n<\/tr>\r\n<tr class=\"a-R\" style=\"height: 25.8pt\">\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 32px;width: 8.02083px\">\r\n<p class=\"import-Normal\">4<\/p>\r\n<\/td>\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 32px;width: 219.312px\">\r\n<p class=\"import-Normal\">It is a quantitative method<\/p>\r\n<\/td>\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 32px;width: 305.125px\">\r\n<p class=\"import-Normal\">It is a semi-quantitative method.<\/p>\r\n<\/td>\r\n<\/tr>\r\n<tr class=\"a-R\" style=\"height: 41.05pt\">\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 61px;width: 8.02083px\">\r\n<p class=\"import-Normal\">5<\/p>\r\n<\/td>\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 61px;width: 219.312px\">\r\n<p class=\"import-Normal\">This technique is generally used to study decomposition reactions.<\/p>\r\n<\/td>\r\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 61px;width: 305.125px\">\r\n<p class=\"import-Normal\">This technique is used to study phase transitions<\/p>\r\n<\/td>\r\n<\/tr>\r\n<tr style=\"height: 10px\">\r\n<td style=\"height: 10px;width: 8.72917px\"><\/td>\r\n<td style=\"height: 10px;width: 220.354px\"><\/td>\r\n<td style=\"height: 10px;width: 305.833px\"><\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<p class=\"import-Normal\"><strong>3.4 Simultaneous TGA\/DTA analysis??? Pending<\/strong><\/p>\r\n<p class=\"import-Normal\"><strong>3.5 Applications???Pending<\/strong><\/p>\r\n<p class=\"import-Normal\"><img src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image6-7.png\" width=\"32.6666666666667px\" height=\"32.6666666666667px\" alt=\"image\" \/><strong>3.6 Game and quiz: pending<\/strong><\/p>\r\n<p class=\"import-Normal\"><\/p>\r\n\r\n<\/div>","rendered":"<div class=\"-3.-differential-thermal-analysis:\">\n<div class=\"textbox textbox--learning-objectives\">\n<header class=\"textbox__header\">\n<h2><strong><img decoding=\"async\" src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image1-8.png\" width=\"34.6666666666667px\" height=\"34.6666666666667px\" alt=\"image\" \/> <\/strong><strong>Learning Objectives<\/strong><\/h2>\n<\/header>\n<div class=\"textbox__content\">\n<p>After going through this Part, you should be able to:<\/p>\n<ul>\n<li class=\"import-Normal\" style=\"text-align: justify\">Explain the principle and working of a differential thermal analyser.<\/li>\n<li class=\"import-Normal\" style=\"text-align: justify\">Draw and interpret DTA thermogram.<\/li>\n<li class=\"import-Normal\" style=\"text-align: justify\">Compare and contrast TG and DTA results.<\/li>\n<li class=\"import-Normal\" style=\"text-align: justify\">Explain the applications of DTA and simultaneous TG-DTA analysis<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<p class=\"import-Normal\" style=\"text-align: justify\">When a molecule undergoes a physical or chemical transition, heat is either absorbed or liberated. Two thermal methods, DTA and DSC are particularly useful for investigating these physical and chemical changes.<\/p>\n<p>&nbsp;<\/p>\n<p><strong style=\"font-size: 1em\">3.1 Principle and Instrumentation:<\/strong><\/p>\n<p class=\"import-Normal\" style=\"text-align: justify\">In DTA, the difference in temperature between the sample and an inert reference (\u2206T) is measured as the sample and the reference are heated or cooled in a controlled manner.<\/p>\n<p class=\"import-Normal\" style=\"text-align: justify\">\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 <a id=\"_3znysh7\"><\/a>\u2206T = T<sub>s<\/sub> \u2013 T<sub>R <\/sub><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 36pt\">T<sub>S <\/sub>= temperature of sample<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 36pt\">T<sub>R<\/sub> = temperature of reference which is thermally stable<\/p>\n<p class=\"import-Normal\">Please go through the <em>Chemlibre<\/em> link to understand the principle and working of DTA.<\/p>\n<p class=\"import-Normal\"><img decoding=\"async\" src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image2-16.png\" width=\"38px\" height=\"28.6666666666667px\" alt=\"image\" \/><a class=\"rId9\" href=\"https:\/\/chem.libretexts.org\/Bookshelves\/Analytical_Chemistry\/Instrumental_Analysis_(LibreTexts)\/31%3A_Thermal_Methods\/31.02%3A_Differential_Thermal_Analysis\">https:\/\/chem.libretexts.org\/Bookshelves\/Analytical_Chemistry\/Instrumental_Analysis_(LibreTexts)\/31%3A_Thermal_Methods\/31.02%3A_Differential_Thermal_Analysis<\/a><\/p>\n<p class=\"import-Normal\"><strong>Instrumentation and working:<\/strong> A typical DTA set up is shown in the figure given below.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 36pt;text-indent: 36pt\"><img decoding=\"async\" src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image3-2.jpg\" width=\"223.749186351706px\" height=\"193.633280839895px\" alt=\"image\" \/><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 36pt;text-indent: 36pt\"><strong>Figure 3.1a.<\/strong> DTA set up<\/p>\n<p class=\"import-Normal\" style=\"text-align: justify\">In differential thermal analysis (DTA), the difference in temperature between the sample and a thermally inert reference material is measured as a function of temperature (usually the sample temperature). Any transition that the sample undergoes results in the liberation or absorption of energy by the sample with a corresponding deviation of its temperature from that of the reference. A plot of the differential temperature, \u0394T, versus the programmed temperature, T, indicates the transition temperature(s) and whether the transition is exothermic or endothermic. DTA and thermogravimetric analyses (measurement of the change in weight as a function of temperature) are often run simultaneously on a single sample.<\/p>\n<p>&nbsp;<\/p>\n<\/div>\n<div class=\"-3.-differential-thermal-analysis:\">\n<p><strong>3.2 DTA curve and its interpretation<\/strong><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 36pt\"><span style=\"margin-left: 26pt\"><\/span>\u2206T = T<sub>s<\/sub> \u2013 T<sub>R <\/sub><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 36pt\">T<sub>s<\/sub>= temperature of sample<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 36pt\">T<sub>R<\/sub> = temperature of reference which is thermally stable<\/p>\n<p class=\"import-Normal\">A typical DTA curve is represented below<\/p>\n<p class=\"import-Normal\">\u00a0 \u00a0 \u00a0 \u00a0 <img decoding=\"async\" src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image4-4.png\" width=\"222\" height=\"313\" alt=\"image\" class=\"\" \/><span style=\"margin-left: 26pt\"><\/span><strong>Figure 3.2a.<\/strong> DTA curve<\/p>\n<p class=\"import-Normal\"><strong><img decoding=\"async\" src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image5-6.png\" width=\"47.3333333333333px\" height=\"47.3333333333333px\" alt=\"image\" \/><\/strong><strong>Brain Teaser:<\/strong><\/p>\n<p class=\"import-Normal\">Can you suggest why we adopt \u2206T &gt; 0 for exothermic and \u2206T &lt; 0 for endothermic transition?<\/p>\n<p class=\"import-Normal\"><img decoding=\"async\" src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image6-5.png\" width=\"32.6666666666667px\" height=\"32.6666666666667px\" alt=\"image\" \/><strong>Activity 3A: <\/strong>The following figure represents thermal investigation. Fill in the blanks by choosing the correct option. (<span style=\"color: #ff6600\">James &amp; Tonge, 2008<\/span>)<\/p>\n<p class=\"import-Normal\"><span style=\"margin-left: 26pt\"><\/span><span style=\"margin-left: 26pt\"><\/span><img decoding=\"async\" src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image7-3.png\" width=\"286.666666666667px\" height=\"134.666666666667px\" alt=\"image\" \/><\/p>\n<p class=\"import-Normal\" style=\"text-align: justify;margin-left: 36pt\">The record shown is that of a_________________ experiment since the_________ plot \u2206T which is a ______________temperature. The ___________direction of the peak indicates that a __________________reaction has occurred. This in turn implies that the corresponding _________________ change \u2206H must have been ____________ ie the value of enthalpy ________________the thermal effect was ____________ than its value _____________.This means that the sample ____________ heat during the reaction. Furthermore, there is evidence of a change _______________in the temperature is increased beyond the thermal transition. This is shown by the ___________of the just beyond the end.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 36pt\"><strong>Answers: Select from the following list<\/strong><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 36pt\">[upward\/downward, free energy\/heat capacity, greater\/less, DTG\/DTA, base-line\/background, derivative\/differential, took in\/gave out, negative\/positive, enthalpy\/entropy, before\/after\/during, exothermic\/endothermic\/isothermal, abscissa\/ordinate, distortion\/displacement.]<\/p>\n<p class=\"import-Normal\"><img decoding=\"async\" src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image6-6.png\" width=\"32.6666666666667px\" height=\"32.6666666666667px\" alt=\"image\" \/><strong>Activity 3B: <\/strong>(<span style=\"color: #ff6600\">James &amp; Tonge, 2008<\/span>)<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 36pt\">During the Falklands campaign in 1982 many naval personnel suffered serious<\/p>\n<p class=\"import-Normal\" style=\"text-indent: 36pt\">burns. In 1985 the Admiralty decreed that all men on active service in Navy<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 36pt\">should be issued cotton uniforms instead of polyester ones which had been<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 36pt\">issued in 1982. Does the thermal data suggest a reason for the decision?<\/p>\n<p class=\"import-Normal\" style=\"text-align: justify\">\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Justify your answer?<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 36pt\"><img decoding=\"async\" src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image8-4.png\" width=\"309.46750656168px\" height=\"189.436220472441px\" alt=\"image\" \/><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 36pt\"><strong> Fig.\u00a0 <\/strong>DTA curves for cotton and polyester -50 mg heated in pure nitrogen at 5\u1d52C min-<sup>1<\/sup><\/p>\n<p>&nbsp;<\/p>\n<\/div>\n<div class=\"-3.-differential-thermal-analysis:\">\n<p><strong>3.3 Comparison with TGA<\/strong><\/p>\n<table style=\"width: 431.85pt;height: 342px\">\n<tbody>\n<tr class=\"a-R\" style=\"height: 19.7pt\">\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 30px;width: 8.02083px\">\n<p class=\"import-Normal\"><strong>\u00a0<\/strong><\/p>\n<\/td>\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 30px;width: 219.312px\">\n<p class=\"import-Normal\"><strong>TGA<\/strong><\/p>\n<\/td>\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 30px;width: 305.125px\">\n<p class=\"import-Normal\"><strong>DTA<\/strong><\/p>\n<\/td>\n<\/tr>\n<tr class=\"a-R\" style=\"height: 61.85pt\">\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 80px;width: 8.02083px\">\n<p class=\"import-Normal\">1<\/p>\n<\/td>\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 80px;width: 219.312px\">\n<p class=\"import-Normal\">It measures change (loss or gain) in weight as the sample is subjected to controlled heating program<\/p>\n<\/td>\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 80px;width: 305.125px\">\n<p class=\"import-Normal\">It is a technique in which the difference in temperature between the sample and an inert reference material, is measured as a function of temperature<\/p>\n<\/td>\n<\/tr>\n<tr class=\"a-R\" style=\"height: 47.8pt\">\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 77px;width: 8.02083px\">\n<p class=\"import-Normal\">2<\/p>\n<\/td>\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 77px;width: 219.312px\">\n<p class=\"import-Normal\">It will detect only those physical and chemical transitions which are accompanied by change in weight.<\/p>\n<\/td>\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 77px;width: 305.125px\">\n<p class=\"import-Normal\">It can detect all physical and chemical transitions.<\/p>\n<\/td>\n<\/tr>\n<tr class=\"a-R\" style=\"height: 41.45pt\">\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 52px;width: 8.02083px\">\n<p class=\"import-Normal\">3<\/p>\n<\/td>\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 52px;width: 219.312px\">\n<p class=\"import-Normal\">This does not require an inert reference.<\/p>\n<\/td>\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 52px;width: 305.125px\">\n<p class=\"import-Normal\">This requires an inert reference material.<\/p>\n<\/td>\n<\/tr>\n<tr class=\"a-R\" style=\"height: 25.8pt\">\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 32px;width: 8.02083px\">\n<p class=\"import-Normal\">4<\/p>\n<\/td>\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 32px;width: 219.312px\">\n<p class=\"import-Normal\">It is a quantitative method<\/p>\n<\/td>\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 32px;width: 305.125px\">\n<p class=\"import-Normal\">It is a semi-quantitative method.<\/p>\n<\/td>\n<\/tr>\n<tr class=\"a-R\" style=\"height: 41.05pt\">\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 61px;width: 8.02083px\">\n<p class=\"import-Normal\">5<\/p>\n<\/td>\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 61px;width: 219.312px\">\n<p class=\"import-Normal\">This technique is generally used to study decomposition reactions.<\/p>\n<\/td>\n<td class=\"a-C\" style=\"background-color: transparent;padding: 0.75pt 4.75pt 0pt;border: 1pt solid #000000;height: 61px;width: 305.125px\">\n<p class=\"import-Normal\">This technique is used to study phase transitions<\/p>\n<\/td>\n<\/tr>\n<tr style=\"height: 10px\">\n<td style=\"height: 10px;width: 8.72917px\"><\/td>\n<td style=\"height: 10px;width: 220.354px\"><\/td>\n<td style=\"height: 10px;width: 305.833px\"><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p class=\"import-Normal\"><strong>3.4 Simultaneous TGA\/DTA analysis??? Pending<\/strong><\/p>\n<p class=\"import-Normal\"><strong>3.5 Applications???Pending<\/strong><\/p>\n<p class=\"import-Normal\"><img decoding=\"async\" src=\"http:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-content\/uploads\/sites\/37\/2024\/05\/image6-7.png\" width=\"32.6666666666667px\" height=\"32.6666666666667px\" alt=\"image\" \/><strong>3.6 Game and quiz: pending<\/strong><\/p>\n<p class=\"import-Normal\">\n<\/div>\n","protected":false},"author":16,"menu_order":3,"template":"","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_uf_show_specific_survey":0,"_uf_disable_surveys":false,"pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"class_list":["post-266","chapter","type-chapter","status-publish","hentry"],"aioseo_notices":[],"part":3,"_links":{"self":[{"href":"https:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-json\/pressbooks\/v2\/chapters\/266","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-json\/wp\/v2\/users\/16"}],"version-history":[{"count":9,"href":"https:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-json\/pressbooks\/v2\/chapters\/266\/revisions"}],"predecessor-version":[{"id":481,"href":"https:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-json\/pressbooks\/v2\/chapters\/266\/revisions\/481"}],"part":[{"href":"https:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-json\/pressbooks\/v2\/parts\/3"}],"metadata":[{"href":"https:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-json\/pressbooks\/v2\/chapters\/266\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-json\/wp\/v2\/media?parent=266"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-json\/pressbooks\/v2\/chapter-type?post=266"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-json\/wp\/v2\/contributor?post=266"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/pressbooks.justwrite.in\/thermalmethodsofanalysis\/wp-json\/wp\/v2\/license?post=266"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}