{"id":2524,"date":"2016-08-23T15:51:34","date_gmt":"2016-08-23T15:51:34","guid":{"rendered":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/?post_type=chapter&#038;p=2524"},"modified":"2017-08-28T21:34:41","modified_gmt":"2017-08-28T21:34:41","slug":"elements-and-compounds","status":"publish","type":"chapter","link":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/chapter\/elements-and-compounds\/","title":{"raw":"Elements and Compounds","rendered":"Elements and Compounds"},"content":{"raw":"<h1 id=\"x-ck12-TWF0dGVyIGFuZCBDaGFuZ2U.-chapter\">Elements<\/h1>\r\n<div class=\"textbox learning-objectives\">\r\n<h3>Learning Objectives<\/h3>\r\n<ul>\r\n \t<li>Define element.<\/li>\r\n \t<li>State basic properties of an element.<\/li>\r\n \t<li>Give examples of elements and their uses.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<div class=\"x-ck12-data-objectives\"><\/div>\r\n<div class=\"textbox examples\">\r\n<h3>Who is Sherlock Holmes?<\/h3>\r\n<p id=\"x-ck12-NDRkZDE5YzVmMTgwMjEyZjRmZDMzOGY5ZjJlODBiMWU.-txr\"><span class=\"x-ck12-img-inline\"><img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19210635\/20140811155007750290.png\" alt=\"Drawing of Sherlock Holmes\" width=\"274\" \/><\/span><\/p>\r\n\r\n<h4 id=\"x-ck12-M2E4N2U1MDg1MDVlOWUyNjliYzQxN2FkNjNjYzAwYTM.-h2v_8-sej\">Who is Sherlock Holmes?<\/h4>\r\n<p id=\"x-ck12-M2E4N2U1MDg1MDVlOWUyNjliYzQxN2FkNjNjYzAwYTM.-opm\">The famous fictional British detective Sherlock Holmes was often said to make the statement \u201celementary, my dear Watson.\u201d In reality, the closest he ever came to that line was an exchange with Watson in the short story \u201cThe Crooked Man.\u201d\u00a0 Holmes shows shrewd insight into Watson\u2019s activities of the day. When asked how he knew what Watson was doing, Holmes simply replies \u201cElementary.\u201d Regardless of exactly how he put it, Sherlock was simply referring to what the Free Dictionary defines as \u201crelating to, or constituting the basic, essential, or fundamental part.\u201d<\/p>\r\n\r\n<\/div>\r\n&nbsp;\r\n<h3>Elements<\/h3>\r\n<p id=\"x-ck12-ZDk0MmE4ZGQxMDY1NGY2ODUyOGMxOGVjMWYzYzk3OGQ.-o52\">An <strong>element <\/strong>is the simplest form of matter that has a unique set of properties. Examples of well-known elements include oxygen, iron, and gold (see the figure below). Elements cannot be broken down into a simpler substance.\u00a0 Likewise, one element cannot be chemically converted into a different element.<\/p>\r\n\r\n<div id=\"x-ck12-YTdhMTg0Zjk2MGI3OWI5M2Y2YTZjZWE2MWUzYzk2MmU.-sbi\" class=\"x-ck12-img-fullpage x-ck12-nofloat\">\r\n<p id=\"x-ck12-h6h\"><img id=\"x-ck12-OTgwNDUtMTM2MzE2MTQwNC02Ny0zNS1JbWFnZS0tLTI2\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19210636\/20140811155007886076.png\" alt=\"An oxygen tank, a cast iron skillet, and gold bars are examples of pure elements\" longdesc=\"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-admin\/Chemical%20elements%20are%20the%20simplest%20of%20substances.%20%28A%29%20An%20oxygen%20tank%20like%20this%20is%20used%20by%20people%20with%20a%20need%20for%20breathing%20assistance.%20%28B%29%20A%20simple%20skillet%20can%20be%20made%20from%20cast%20iron.%20%28C%29%20Gold%20bars%20are%20formed%20and%20used%20for%20monetary%20purposes.\" \/><\/p>\r\n<strong>Figure 2.14<\/strong>\r\n<p id=\"x-ck12-Y2EyMmQyYjQ4NTU1N2FlM2YyMDY4MDUxZTU4NmQxMTA.-stj\">Chemical elements are the simplest of substances. (A) An oxygen tank like this is used by people with a need for breathing assistance. (B) A simple skillet can be made from cast iron. (C) Gold bars are formed and used for monetary purposes.<\/p>\r\n\r\n<\/div>\r\n<p id=\"x-ck12-YjlmMTI2MjM5NGMxMjY0YWEzMGVjZjMyNTJhMmU5YTk.-au4\">Some elements have been known for centuries (gold, silver, iron, copper, among others) while others have been created in the lab only within the last several years. Most elements do not exist as such in nature. They are so reactive that they can be found only in combination with other materials.<\/p>\r\n<p id=\"x-ck12-Zjc2MjNhZTY2OTg1ZmE2Y2U1MTVmN2UzNjQ5MjM3Y2Y.-x9l\">Several of the elements are very valuable while others are quite inexpensive. Gold is currently worth almost $1700 per ounce. Aluminum, on the other hand, only sells for about 90 cents per pound, considerably lower than gold. Copper is worth somewhat more, selling for approximately $3.50 pound. Platinum is very valuable at about $1650 an ounce, not quite as expensive as gold.<\/p>\r\n<p id=\"x-ck12-YmMzNTQ4OGU5ODNmNmY3N2MyOGNmYzQ1NjFmOTliMDc.-mcv\">Enjoy an old song about the elements sung by Harvard lecturer Tom Lehrer. There were only 102 known elements at the time he wrote this song.<\/p>\r\nhttps:\/\/youtu.be\/K8eT-k4f7_8\r\n<div class=\"textbox key-takeaways\">\r\n<h3>Summary<\/h3>\r\n<ul id=\"x-ck12-YTllZGMzYTFiYjY1M2JhM2NlNDgyMzAyZjkyMWIzYmY.-1qw\">\r\n \t<li>An element is the simplest form of matter that has a unique set of properties.<\/li>\r\n \t<li>One element cannot be chemically converted to another element.<\/li>\r\n<\/ul>\r\n<\/div>\r\n&nbsp;\r\n<div class=\"textbox exercises\">\r\n<h3>Practice<\/h3>\r\n<p id=\"x-ck12-NmNlM2JkYzM5ZTU0NDcyNTAzOGUwZTg3Yjc3MWRiMWU.-kwp\" dir=\"ltr\"><em>Questions<\/em><\/p>\r\n<p id=\"x-ck12-YjEzYWU0MGYxMzY2MjM1ZGMyYWQ3MGMwZjk5OGJlNjk.-aaz\">Select an element from this list:<\/p>\r\n<p id=\"x-ck12-MWRhMDg4NDM3NWZkNTMzOWJkOWEwNmI0NDI5OWU1NDQ.-zlf\"><a href=\"http:\/\/www.lenntech.com\/periodic\/name\/alphabetic.htm\">http:\/\/www.lenntech.com\/periodic\/name\/alphabetic.htm<\/a><\/p>\r\n<p id=\"x-ck12-MTI3YzdmNDk2YzI3ZDg2MjU0MDEwMzQ5YTIzMTFmMGU.-g8g\">Answer the following questions:<\/p>\r\n\r\n<ol id=\"x-ck12-YjJjMTI4ZmM0NjczODVlZGY3NWRjOWNiNWExZTA4Y2U.-h9r\">\r\n \t<li>What is the name of the element?<\/li>\r\n \t<li>When was it discovered?<\/li>\r\n \t<li>Who discovered it?<\/li>\r\n \t<li>What is one use for this element?<\/li>\r\n<\/ol>\r\n<\/div>\r\n&nbsp;\r\n<div class=\"textbox exercises\">\r\n<h3>Review<\/h3>\r\n<p id=\"x-ck12-NmNlM2JkYzM5ZTU0NDcyNTAzOGUwZTg3Yjc3MWRiMWU.-jez\" dir=\"ltr\"><em>Questions<\/em><\/p>\r\n\r\n<ol id=\"x-ck12-NmMwNTE4MTFmYzE3NWU1YmUwMjFlNGQ0ZWFmYzZiNjc.-9z7\">\r\n \t<li>What is an element?<\/li>\r\n \t<li>How much is gold worth today?<\/li>\r\n \t<li>How many elements did we know about when Tom Lehrer wrote his song?<\/li>\r\n<\/ol>\r\n<\/div>\r\n&nbsp;\r\n<div class=\"x-ck12-data-problem-set\">\r\n<h2>Glossary<\/h2>\r\n<\/div>\r\n<div class=\"x-ck12-data-vocabulary\">\r\n<ul id=\"x-ck12-ZDNjYjg4NTBhODBhZDMyNzJkY2FiM2U1NjA2MTBmZGE.-fln\">\r\n \t<li><strong>element: <\/strong>The simplest form of matter that has a unique set of properties.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<h1 id=\"x-ck12-Q29tcG91bmRz\">Compounds<\/h1>\r\n<div class=\"textbox learning-objectives\">\r\n<h3>Learning Objectives<\/h3>\r\n<ul>\r\n \t<li>Define compound distinguish between element and compound.<\/li>\r\n \t<li>Give examples of compounds.<\/li>\r\n \t<li>Define chemical change.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<div class=\"x-ck12-data-objectives\"><\/div>\r\n<div class=\"textbox examples\">\r\n<h3>What do you need to start building a house?<\/h3>\r\n<p id=\"x-ck12-YzVmNTgzOWI4ZmFkZmE1NzhjNjdmNGMyMDZhZDhlZWU.-rtq\"><span class=\"x-ck12-img-inline\"><img src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19210639\/20140811155008075900.jpeg\" alt=\"Benefits: Khadi face pack neem will help your skin get rid of the daily build up of toxins underneath your skin and at the same get rid of bacteria, germs and dirt embedded in your skin to give it a healthy glow. Key Ingredients: Fuller\u2019s earth, neem, tulsi, lodhra, tea tree oil.\" width=\"350\" \/><\/span><\/p>\r\n<p id=\"x-ck12-NWE2ZmJmYmVkMTUxYzY3YWNlNmM4NTNkZjE5NGU3ZDQ.-qbg\"><strong>What do you need to start building a house?<\/strong><\/p>\r\n<p id=\"x-ck12-NjRiOTIwZDliYTNjYTI2ODBkNjc5OWIwODYxNTY1MzM.-rr5\">When building a house, you start with a blueprint of what the house will look like.\u00a0 The plan states how many windows and what kind, how many doors and what style, how many rooms and what type (bedroom, kitchen, other).\u00a0 The blueprint shows how the different pieces will go together to make the house.\u00a0 As long as the blueprint is followed and exactly the same items are used, the houses will be identical.<\/p>\r\n\r\n<\/div>\r\n&nbsp;\r\n<h3>Compounds<\/h3>\r\n<p id=\"x-ck12-ZDQ2OGE0MTY3MzE3ZDM5YWU2ZjU1NjNiZDhmOTBkMDc.-m2d\">A <strong>compound <\/strong>is a substance that contains two or more elements chemically combined in a fixed proportion.\u00a0 The elements carbon and hydrogen combine to form many different compounds.\u00a0 One of the simplest is called methane, in which there are always four times as many hydrogen particles as carbon particles.\u00a0 Methane is a pure substance because it always has the same composition.\u00a0 However, it is not an element because it can be broken down into simpler substances \u2013 carbon and hydrogen.<\/p>\r\n<p id=\"x-ck12-ZTY3ZGU4NzZhYjljZjQxYjQ0NTVkZDZiNTQ4YzVlYWM.-afw\">Recall that the components of a mixture can be separated from one another by physical means.\u00a0 This is not true for a compound.\u00a0 Table salt is a compound consisting of equal parts of the elements sodium and chlorine.\u00a0 Salt cannot be separated into its two elements by filtering, distillation, or any other physical process.\u00a0 Salt and other compounds can only be decomposed into their elements by a chemical process.\u00a0 A <strong>chemical change <\/strong>is a change that produces matter with a different composition.\u00a0 Many compounds can be decomposed into their elements by heating.\u00a0 When sugar is heated, it decomposes to carbon and water.\u00a0 Water is still a compound, but one which cannot be broken down into hydrogen and oxygen by heating.\u00a0 Instead, the passage of an electrical current through water will produce hydrogen and oxygen gases.<\/p>\r\n<p id=\"x-ck12-NjU2ZjNiMjBmMDg3ZTMyYTcxYTcxZThkYWQyOWViNmQ.-sbi\">The properties of compounds are generally very different than the properties of the elements from which the compound is formed.\u00a0 Sodium is an extremely reactive soft metal that cannot be exposed to air or water.\u00a0 Chlorine is a deadly gas.\u00a0 The compound sodium chloride is a white solid which is essential for all living things ( <strong>Figure <\/strong>below ).<\/p>\r\n\r\n<div id=\"x-ck12-MWI2NTExN2MyYmE1MTU0ZTEzNTc5OTBkOGVmMzFiNzk.-6vz\" class=\"x-ck12-img-postcard x-ck12-nofloat\">\r\n<p id=\"x-ck12-1vb\"><img id=\"x-ck12-OTgwNDUtMTM2MzE2MTg0MS0yNy00Ni1JbWFnZS0tLTI4\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19210640\/20140811155008236618.png\" alt=\"Sodium and chlorine combine to make sodium chloride, table salt\" longdesc=\"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-admin\/%28A%29%20Sodium%20is%20so%20reactive%20that%20it%20must%20be%20stored%20under%20oil.%20%28B%29%20Chlorine%20is%20a%20poisonous%20yellow-green%20gas.%20%28C%29%20Salt%20crystals%2C%20a%20compound%20of%20sodium%20and%20chlorine\" \/><\/p>\r\n<strong>Figure 2.15<\/strong>\r\n<p id=\"x-ck12-N2M3MGE5YmRkYzM4MDgzM2MxMDIzNDViMzljY2U4ZTc.-roq\">(A) Sodium is so reactive that it must be stored under oil. (B) Chlorine is a poisonous yellow-green gas. (C) Salt crystals, a compound of sodium and chlorine<\/p>\r\n\r\n<\/div>\r\n<div class=\"textbox key-takeaways\">\r\n<h3>Summary<\/h3>\r\n<ol id=\"x-ck12-ZjRhY2M4YzA5MTgzMGI4M2IxZmM3ZjI2ODczY2ZkN2Y.-pkv\">\r\n \t<li>A compound is a substance that contains two or more elements chemically combined in a fixed proportion.<\/li>\r\n \t<li>A chemical change is a change that produces matter with a different composition.<\/li>\r\n<\/ol>\r\n<\/div>\r\n&nbsp;\r\n<div class=\"textbox exercises\">\r\n<h3>Practice<\/h3>\r\n<p id=\"x-ck12-NmNlM2JkYzM5ZTU0NDcyNTAzOGUwZTg3Yjc3MWRiMWU.-5zc\" dir=\"ltr\"><em>Questions<\/em><\/p>\r\n<p id=\"x-ck12-OTI0OTYzZGQ2Y2U0ODVmOWFlNWNhMTQ0MmUwMmVhNzc.-5vd\">Watch the video at the link below to answer the following questions:<\/p>\r\nhttps:\/\/youtu.be\/9YPvwsDeLUo\r\n<ol id=\"x-ck12-MzI1YjQ0YmU3ZDIyNzBkODYyMTYxNTc0MDc4NTkyMDI.-i8y\">\r\n \t<li>What lists all the elements we know about?<\/li>\r\n \t<li>What is the compound made out of two hydrogen atoms and one oxygen atom?<\/li>\r\n \t<li>What is the compound made out of one carbon atom and two oxygen atoms?<\/li>\r\n<\/ol>\r\n<\/div>\r\n&nbsp;\r\n<div class=\"textbox exercises\">\r\n<h3>Review<\/h3>\r\n<p id=\"x-ck12-NmNlM2JkYzM5ZTU0NDcyNTAzOGUwZTg3Yjc3MWRiMWU.-c02\" dir=\"ltr\"><em>Questions<\/em><\/p>\r\n\r\n<ol id=\"x-ck12-ZGU5ZGFkYWM1YzhlMjAxMDFiNDhjM2VlNWIwNGZjNzU.-rac\">\r\n \t<li>What is a compound?<\/li>\r\n \t<li>How is a compound different from an element?<\/li>\r\n \t<li>What is a chemical change?<\/li>\r\n<\/ol>\r\n<\/div>\r\n&nbsp;\r\n<div class=\"x-ck12-data-problem-set\">\r\n<h2>Glossary<\/h2>\r\n<\/div>\r\n<div class=\"x-ck12-data-vocabulary\">\r\n<ul id=\"x-ck12-ZWRlODA0OGMyM2Y3MWMzMTgyYWZlNzRlNWZiMjY1MTM.-tux\">\r\n \t<li><strong>chemical change: <\/strong>A change that produces matter with a different composition.<\/li>\r\n \t<li><strong>compound: <\/strong>A substance that contains two or more elements chemically combined in a fixed proportion.<\/li>\r\n<\/ul>\r\n<\/div>\r\n[reveal-answer q=\"836080\"]Show References[\/reveal-answer]\r\n[hidden-answer a=\"836080\"]\r\n<h2>References<\/h2>\r\n<ol>\r\n \t<li>Sidney Paget. <a href=\"http:\/\/commons.wikimedia.org\/wiki\/File:Paget_holmes.png\">http:\/\/commons.wikimedia.org\/wiki\/File:Paget_holmes.png <\/a>.<\/li>\r\n \t<li>(A) Leon Brocard (Flickr: acme); (B) User:Evan-Amos\/Wikimedia Commons; (C) Agnico-Eagle Mines Limited. (A) http:\/\/www.flickr.com\/photos\/acme\/8532536\/; (B) http:\/\/commons.wikimedia.org\/wiki\/File:Cast-Iron-Pan.jpg; (C) http:\/\/commons.wikimedia.org\/wiki\/File:Gold_Bars.jpg .<\/li>\r\n \t<li>User:JohnABerring27A\/Wikipedia. <a href=\"http:\/\/commons.wikimedia.org\/wiki\/File:Ferris_Bueller_house_southeast_view.jpg\">http:\/\/commons.wikimedia.org\/wiki\/File:Ferris_Bueller_house_southeast_view.jpg <\/a>.<\/li>\r\n \t<li>(A) Hi-Res Images of Chemical Elements; (B) User:Greenhorn1\/Wikimedia Commons; (C) User:Miansari66\/Wikimedia Commons. (A) http:\/\/images-of-elements.com\/sodium.php; (B) http:\/\/commons.wikimedia.org\/wiki\/File:Chlorine2.jpg; (C) http:\/\/commons.wikimedia.org\/wiki\/File:Salt_,_Lake_salt.JPG .<\/li>\r\n<\/ol>\r\n[\/hidden-answer]","rendered":"<h1 id=\"x-ck12-TWF0dGVyIGFuZCBDaGFuZ2U.-chapter\">Elements<\/h1>\n<div class=\"textbox learning-objectives\">\n<h3>Learning Objectives<\/h3>\n<ul>\n<li>Define element.<\/li>\n<li>State basic properties of an element.<\/li>\n<li>Give examples of elements and their uses.<\/li>\n<\/ul>\n<\/div>\n<div class=\"x-ck12-data-objectives\"><\/div>\n<div class=\"textbox examples\">\n<h3>Who is Sherlock Holmes?<\/h3>\n<p id=\"x-ck12-NDRkZDE5YzVmMTgwMjEyZjRmZDMzOGY5ZjJlODBiMWU.-txr\"><span class=\"x-ck12-img-inline\"><img decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19210635\/20140811155007750290.png\" alt=\"Drawing of Sherlock Holmes\" width=\"274\" \/><\/span><\/p>\n<h4 id=\"x-ck12-M2E4N2U1MDg1MDVlOWUyNjliYzQxN2FkNjNjYzAwYTM.-h2v_8-sej\">Who is Sherlock Holmes?<\/h4>\n<p id=\"x-ck12-M2E4N2U1MDg1MDVlOWUyNjliYzQxN2FkNjNjYzAwYTM.-opm\">The famous fictional British detective Sherlock Holmes was often said to make the statement \u201celementary, my dear Watson.\u201d In reality, the closest he ever came to that line was an exchange with Watson in the short story \u201cThe Crooked Man.\u201d\u00a0 Holmes shows shrewd insight into Watson\u2019s activities of the day. When asked how he knew what Watson was doing, Holmes simply replies \u201cElementary.\u201d Regardless of exactly how he put it, Sherlock was simply referring to what the Free Dictionary defines as \u201crelating to, or constituting the basic, essential, or fundamental part.\u201d<\/p>\n<\/div>\n<p>&nbsp;<\/p>\n<h3>Elements<\/h3>\n<p id=\"x-ck12-ZDk0MmE4ZGQxMDY1NGY2ODUyOGMxOGVjMWYzYzk3OGQ.-o52\">An <strong>element <\/strong>is the simplest form of matter that has a unique set of properties. Examples of well-known elements include oxygen, iron, and gold (see the figure below). Elements cannot be broken down into a simpler substance.\u00a0 Likewise, one element cannot be chemically converted into a different element.<\/p>\n<div id=\"x-ck12-YTdhMTg0Zjk2MGI3OWI5M2Y2YTZjZWE2MWUzYzk2MmU.-sbi\" class=\"x-ck12-img-fullpage x-ck12-nofloat\">\n<p id=\"x-ck12-h6h\"><img decoding=\"async\" id=\"x-ck12-OTgwNDUtMTM2MzE2MTQwNC02Ny0zNS1JbWFnZS0tLTI2\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19210636\/20140811155007886076.png\" alt=\"An oxygen tank, a cast iron skillet, and gold bars are examples of pure elements\" longdesc=\"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-admin\/Chemical%20elements%20are%20the%20simplest%20of%20substances.%20%28A%29%20An%20oxygen%20tank%20like%20this%20is%20used%20by%20people%20with%20a%20need%20for%20breathing%20assistance.%20%28B%29%20A%20simple%20skillet%20can%20be%20made%20from%20cast%20iron.%20%28C%29%20Gold%20bars%20are%20formed%20and%20used%20for%20monetary%20purposes.\" \/><\/p>\n<p><strong>Figure 2.14<\/strong><\/p>\n<p id=\"x-ck12-Y2EyMmQyYjQ4NTU1N2FlM2YyMDY4MDUxZTU4NmQxMTA.-stj\">Chemical elements are the simplest of substances. (A) An oxygen tank like this is used by people with a need for breathing assistance. (B) A simple skillet can be made from cast iron. (C) Gold bars are formed and used for monetary purposes.<\/p>\n<\/div>\n<p id=\"x-ck12-YjlmMTI2MjM5NGMxMjY0YWEzMGVjZjMyNTJhMmU5YTk.-au4\">Some elements have been known for centuries (gold, silver, iron, copper, among others) while others have been created in the lab only within the last several years. Most elements do not exist as such in nature. They are so reactive that they can be found only in combination with other materials.<\/p>\n<p id=\"x-ck12-Zjc2MjNhZTY2OTg1ZmE2Y2U1MTVmN2UzNjQ5MjM3Y2Y.-x9l\">Several of the elements are very valuable while others are quite inexpensive. Gold is currently worth almost $1700 per ounce. Aluminum, on the other hand, only sells for about 90 cents per pound, considerably lower than gold. Copper is worth somewhat more, selling for approximately $3.50 pound. Platinum is very valuable at about $1650 an ounce, not quite as expensive as gold.<\/p>\n<p id=\"x-ck12-YmMzNTQ4OGU5ODNmNmY3N2MyOGNmYzQ1NjFmOTliMDc.-mcv\">Enjoy an old song about the elements sung by Harvard lecturer Tom Lehrer. There were only 102 known elements at the time he wrote this song.<\/p>\n<p><iframe loading=\"lazy\" id=\"oembed-1\" title=\"The Chemical elements song\" width=\"500\" height=\"375\" src=\"https:\/\/www.youtube.com\/embed\/K8eT-k4f7_8?feature=oembed&#38;rel=0\" frameborder=\"0\" allowfullscreen=\"allowfullscreen\"><\/iframe><\/p>\n<div class=\"textbox key-takeaways\">\n<h3>Summary<\/h3>\n<ul id=\"x-ck12-YTllZGMzYTFiYjY1M2JhM2NlNDgyMzAyZjkyMWIzYmY.-1qw\">\n<li>An element is the simplest form of matter that has a unique set of properties.<\/li>\n<li>One element cannot be chemically converted to another element.<\/li>\n<\/ul>\n<\/div>\n<p>&nbsp;<\/p>\n<div class=\"textbox exercises\">\n<h3>Practice<\/h3>\n<p id=\"x-ck12-NmNlM2JkYzM5ZTU0NDcyNTAzOGUwZTg3Yjc3MWRiMWU.-kwp\" dir=\"ltr\"><em>Questions<\/em><\/p>\n<p id=\"x-ck12-YjEzYWU0MGYxMzY2MjM1ZGMyYWQ3MGMwZjk5OGJlNjk.-aaz\">Select an element from this list:<\/p>\n<p id=\"x-ck12-MWRhMDg4NDM3NWZkNTMzOWJkOWEwNmI0NDI5OWU1NDQ.-zlf\"><a href=\"http:\/\/www.lenntech.com\/periodic\/name\/alphabetic.htm\">http:\/\/www.lenntech.com\/periodic\/name\/alphabetic.htm<\/a><\/p>\n<p id=\"x-ck12-MTI3YzdmNDk2YzI3ZDg2MjU0MDEwMzQ5YTIzMTFmMGU.-g8g\">Answer the following questions:<\/p>\n<ol id=\"x-ck12-YjJjMTI4ZmM0NjczODVlZGY3NWRjOWNiNWExZTA4Y2U.-h9r\">\n<li>What is the name of the element?<\/li>\n<li>When was it discovered?<\/li>\n<li>Who discovered it?<\/li>\n<li>What is one use for this element?<\/li>\n<\/ol>\n<\/div>\n<p>&nbsp;<\/p>\n<div class=\"textbox exercises\">\n<h3>Review<\/h3>\n<p id=\"x-ck12-NmNlM2JkYzM5ZTU0NDcyNTAzOGUwZTg3Yjc3MWRiMWU.-jez\" dir=\"ltr\"><em>Questions<\/em><\/p>\n<ol id=\"x-ck12-NmMwNTE4MTFmYzE3NWU1YmUwMjFlNGQ0ZWFmYzZiNjc.-9z7\">\n<li>What is an element?<\/li>\n<li>How much is gold worth today?<\/li>\n<li>How many elements did we know about when Tom Lehrer wrote his song?<\/li>\n<\/ol>\n<\/div>\n<p>&nbsp;<\/p>\n<div class=\"x-ck12-data-problem-set\">\n<h2>Glossary<\/h2>\n<\/div>\n<div class=\"x-ck12-data-vocabulary\">\n<ul id=\"x-ck12-ZDNjYjg4NTBhODBhZDMyNzJkY2FiM2U1NjA2MTBmZGE.-fln\">\n<li><strong>element: <\/strong>The simplest form of matter that has a unique set of properties.<\/li>\n<\/ul>\n<\/div>\n<h1 id=\"x-ck12-Q29tcG91bmRz\">Compounds<\/h1>\n<div class=\"textbox learning-objectives\">\n<h3>Learning Objectives<\/h3>\n<ul>\n<li>Define compound distinguish between element and compound.<\/li>\n<li>Give examples of compounds.<\/li>\n<li>Define chemical change.<\/li>\n<\/ul>\n<\/div>\n<div class=\"x-ck12-data-objectives\"><\/div>\n<div class=\"textbox examples\">\n<h3>What do you need to start building a house?<\/h3>\n<p id=\"x-ck12-YzVmNTgzOWI4ZmFkZmE1NzhjNjdmNGMyMDZhZDhlZWU.-rtq\"><span class=\"x-ck12-img-inline\"><img decoding=\"async\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19210639\/20140811155008075900.jpeg\" alt=\"Benefits: Khadi face pack neem will help your skin get rid of the daily build up of toxins underneath your skin and at the same get rid of bacteria, germs and dirt embedded in your skin to give it a healthy glow. Key Ingredients: Fuller\u2019s earth, neem, tulsi, lodhra, tea tree oil.\" width=\"350\" \/><\/span><\/p>\n<p id=\"x-ck12-NWE2ZmJmYmVkMTUxYzY3YWNlNmM4NTNkZjE5NGU3ZDQ.-qbg\"><strong>What do you need to start building a house?<\/strong><\/p>\n<p id=\"x-ck12-NjRiOTIwZDliYTNjYTI2ODBkNjc5OWIwODYxNTY1MzM.-rr5\">When building a house, you start with a blueprint of what the house will look like.\u00a0 The plan states how many windows and what kind, how many doors and what style, how many rooms and what type (bedroom, kitchen, other).\u00a0 The blueprint shows how the different pieces will go together to make the house.\u00a0 As long as the blueprint is followed and exactly the same items are used, the houses will be identical.<\/p>\n<\/div>\n<p>&nbsp;<\/p>\n<h3>Compounds<\/h3>\n<p id=\"x-ck12-ZDQ2OGE0MTY3MzE3ZDM5YWU2ZjU1NjNiZDhmOTBkMDc.-m2d\">A <strong>compound <\/strong>is a substance that contains two or more elements chemically combined in a fixed proportion.\u00a0 The elements carbon and hydrogen combine to form many different compounds.\u00a0 One of the simplest is called methane, in which there are always four times as many hydrogen particles as carbon particles.\u00a0 Methane is a pure substance because it always has the same composition.\u00a0 However, it is not an element because it can be broken down into simpler substances \u2013 carbon and hydrogen.<\/p>\n<p id=\"x-ck12-ZTY3ZGU4NzZhYjljZjQxYjQ0NTVkZDZiNTQ4YzVlYWM.-afw\">Recall that the components of a mixture can be separated from one another by physical means.\u00a0 This is not true for a compound.\u00a0 Table salt is a compound consisting of equal parts of the elements sodium and chlorine.\u00a0 Salt cannot be separated into its two elements by filtering, distillation, or any other physical process.\u00a0 Salt and other compounds can only be decomposed into their elements by a chemical process.\u00a0 A <strong>chemical change <\/strong>is a change that produces matter with a different composition.\u00a0 Many compounds can be decomposed into their elements by heating.\u00a0 When sugar is heated, it decomposes to carbon and water.\u00a0 Water is still a compound, but one which cannot be broken down into hydrogen and oxygen by heating.\u00a0 Instead, the passage of an electrical current through water will produce hydrogen and oxygen gases.<\/p>\n<p id=\"x-ck12-NjU2ZjNiMjBmMDg3ZTMyYTcxYTcxZThkYWQyOWViNmQ.-sbi\">The properties of compounds are generally very different than the properties of the elements from which the compound is formed.\u00a0 Sodium is an extremely reactive soft metal that cannot be exposed to air or water.\u00a0 Chlorine is a deadly gas.\u00a0 The compound sodium chloride is a white solid which is essential for all living things ( <strong>Figure <\/strong>below ).<\/p>\n<div id=\"x-ck12-MWI2NTExN2MyYmE1MTU0ZTEzNTc5OTBkOGVmMzFiNzk.-6vz\" class=\"x-ck12-img-postcard x-ck12-nofloat\">\n<p id=\"x-ck12-1vb\"><img decoding=\"async\" id=\"x-ck12-OTgwNDUtMTM2MzE2MTg0MS0yNy00Ni1JbWFnZS0tLTI4\" src=\"https:\/\/s3-us-west-2.amazonaws.com\/courses-images-archive-read-only\/wp-content\/uploads\/sites\/53\/2014\/08\/19210640\/20140811155008236618.png\" alt=\"Sodium and chlorine combine to make sodium chloride, table salt\" longdesc=\"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-admin\/%28A%29%20Sodium%20is%20so%20reactive%20that%20it%20must%20be%20stored%20under%20oil.%20%28B%29%20Chlorine%20is%20a%20poisonous%20yellow-green%20gas.%20%28C%29%20Salt%20crystals%2C%20a%20compound%20of%20sodium%20and%20chlorine\" \/><\/p>\n<p><strong>Figure 2.15<\/strong><\/p>\n<p id=\"x-ck12-N2M3MGE5YmRkYzM4MDgzM2MxMDIzNDViMzljY2U4ZTc.-roq\">(A) Sodium is so reactive that it must be stored under oil. (B) Chlorine is a poisonous yellow-green gas. (C) Salt crystals, a compound of sodium and chlorine<\/p>\n<\/div>\n<div class=\"textbox key-takeaways\">\n<h3>Summary<\/h3>\n<ol id=\"x-ck12-ZjRhY2M4YzA5MTgzMGI4M2IxZmM3ZjI2ODczY2ZkN2Y.-pkv\">\n<li>A compound is a substance that contains two or more elements chemically combined in a fixed proportion.<\/li>\n<li>A chemical change is a change that produces matter with a different composition.<\/li>\n<\/ol>\n<\/div>\n<p>&nbsp;<\/p>\n<div class=\"textbox exercises\">\n<h3>Practice<\/h3>\n<p id=\"x-ck12-NmNlM2JkYzM5ZTU0NDcyNTAzOGUwZTg3Yjc3MWRiMWU.-5zc\" dir=\"ltr\"><em>Questions<\/em><\/p>\n<p id=\"x-ck12-OTI0OTYzZGQ2Y2U0ODVmOWFlNWNhMTQ0MmUwMmVhNzc.-5vd\">Watch the video at the link below to answer the following questions:<\/p>\n<p><iframe loading=\"lazy\" id=\"oembed-2\" title=\"Chemical Compounds\" width=\"500\" height=\"375\" src=\"https:\/\/www.youtube.com\/embed\/9YPvwsDeLUo?feature=oembed&#38;rel=0\" frameborder=\"0\" allowfullscreen=\"allowfullscreen\"><\/iframe><\/p>\n<ol id=\"x-ck12-MzI1YjQ0YmU3ZDIyNzBkODYyMTYxNTc0MDc4NTkyMDI.-i8y\">\n<li>What lists all the elements we know about?<\/li>\n<li>What is the compound made out of two hydrogen atoms and one oxygen atom?<\/li>\n<li>What is the compound made out of one carbon atom and two oxygen atoms?<\/li>\n<\/ol>\n<\/div>\n<p>&nbsp;<\/p>\n<div class=\"textbox exercises\">\n<h3>Review<\/h3>\n<p id=\"x-ck12-NmNlM2JkYzM5ZTU0NDcyNTAzOGUwZTg3Yjc3MWRiMWU.-c02\" dir=\"ltr\"><em>Questions<\/em><\/p>\n<ol id=\"x-ck12-ZGU5ZGFkYWM1YzhlMjAxMDFiNDhjM2VlNWIwNGZjNzU.-rac\">\n<li>What is a compound?<\/li>\n<li>How is a compound different from an element?<\/li>\n<li>What is a chemical change?<\/li>\n<\/ol>\n<\/div>\n<p>&nbsp;<\/p>\n<div class=\"x-ck12-data-problem-set\">\n<h2>Glossary<\/h2>\n<\/div>\n<div class=\"x-ck12-data-vocabulary\">\n<ul id=\"x-ck12-ZWRlODA0OGMyM2Y3MWMzMTgyYWZlNzRlNWZiMjY1MTM.-tux\">\n<li><strong>chemical change: <\/strong>A change that produces matter with a different composition.<\/li>\n<li><strong>compound: <\/strong>A substance that contains two or more elements chemically combined in a fixed proportion.<\/li>\n<\/ul>\n<\/div>\n<div class=\"qa-wrapper\" style=\"display: block\"><span class=\"show-answer collapsed\" style=\"cursor: pointer\" data-target=\"q836080\">Show References<\/span><\/p>\n<div id=\"q836080\" class=\"hidden-answer\" style=\"display: none\">\n<h2>References<\/h2>\n<ol>\n<li>Sidney Paget. <a href=\"http:\/\/commons.wikimedia.org\/wiki\/File:Paget_holmes.png\">http:\/\/commons.wikimedia.org\/wiki\/File:Paget_holmes.png <\/a>.<\/li>\n<li>(A) Leon Brocard (Flickr: acme); (B) User:Evan-Amos\/Wikimedia Commons; (C) Agnico-Eagle Mines Limited. (A) http:\/\/www.flickr.com\/photos\/acme\/8532536\/; (B) http:\/\/commons.wikimedia.org\/wiki\/File:Cast-Iron-Pan.jpg; (C) http:\/\/commons.wikimedia.org\/wiki\/File:Gold_Bars.jpg .<\/li>\n<li>User:JohnABerring27A\/Wikipedia. <a href=\"http:\/\/commons.wikimedia.org\/wiki\/File:Ferris_Bueller_house_southeast_view.jpg\">http:\/\/commons.wikimedia.org\/wiki\/File:Ferris_Bueller_house_southeast_view.jpg <\/a>.<\/li>\n<li>(A) Hi-Res Images of Chemical Elements; (B) User:Greenhorn1\/Wikimedia Commons; (C) User:Miansari66\/Wikimedia Commons. (A) http:\/\/images-of-elements.com\/sodium.php; (B) http:\/\/commons.wikimedia.org\/wiki\/File:Chlorine2.jpg; (C) http:\/\/commons.wikimedia.org\/wiki\/File:Salt_,_Lake_salt.JPG .<\/li>\n<\/ol>\n<\/div>\n<\/div>\n","protected":false},"author":1507,"menu_order":7,"template":"","meta":{"_candela_citation":"[]","CANDELA_OUTCOMES_GUID":"","pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"class_list":["post-2524","chapter","type-chapter","status-publish","hentry"],"part":2324,"_links":{"self":[{"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/pressbooks\/v2\/chapters\/2524","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/wp\/v2\/users\/1507"}],"version-history":[{"count":7,"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/pressbooks\/v2\/chapters\/2524\/revisions"}],"predecessor-version":[{"id":3582,"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/pressbooks\/v2\/chapters\/2524\/revisions\/3582"}],"part":[{"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/pressbooks\/v2\/parts\/2324"}],"metadata":[{"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/pressbooks\/v2\/chapters\/2524\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/wp\/v2\/media?parent=2524"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/pressbooks\/v2\/chapter-type?post=2524"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/wp\/v2\/contributor?post=2524"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/courses.lumenlearning.com\/umes-cheminter\/wp-json\/wp\/v2\/license?post=2524"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}