{"id":3647,"date":"2023-01-09T10:09:58","date_gmt":"2023-01-09T10:09:58","guid":{"rendered":"https:\/\/9thclass.deltapublications.in\/?page_id=3647"},"modified":"2025-01-06T17:10:25","modified_gmt":"2025-01-06T17:10:25","slug":"s-3-d-writing-chemical-formulae","status":"publish","type":"page","link":"https:\/\/9thclass.deltapublications.in\/index.php\/s-3-d-writing-chemical-formulae\/","title":{"rendered":"S-3.d Writing Chemical \u00a0Formulae"},"content":{"rendered":"\n<h2 class=\"wp-block-heading has-text-align-center has-text-color\" style=\"color:#00056d;text-transform:uppercase\"><strong>Writing Chemical &nbsp;Formulae<\/strong><\/h2>\n\n\n\n<p class=\"has-text-color has-huge-font-size\" style=\"color:#74008b\"><strong>Key Notes:<\/strong><\/p>\n\n\n\n<p class=\"has-text-align-center has-text-color has-background has-link-color has-large-font-size wp-elements-cd61d4b0884b398b842fb623aac8f70c\" style=\"color:#000060;background-color:#dfc816\"><strong>Definition of Chemical Formula<\/strong>:<\/p>\n\n\n\n<ul class=\"has-large-font-size wp-block-list\">\n<li>A chemical formula represents the elements in a compound and their relative proportions.<\/li>\n\n\n\n<li>It consists of symbols for elements and subscripts indicating the number of atoms of each element in the molecule.<\/li>\n<\/ul>\n\n\n\n<p class=\"has-text-align-center has-text-color has-background has-link-color has-large-font-size wp-elements-e029f152e468392c47679be6d1525bd8\" style=\"color:#000060;background-color:#dfc816\"><strong>Symbols of Elements<\/strong>:<\/p>\n\n\n\n<ul class=\"has-large-font-size wp-block-list\">\n<li>Every element has a unique symbol (e.g., H for hydrogen, O for oxygen, Na for sodium).<\/li>\n\n\n\n<li>These symbols are used in writing chemical formulas.<\/li>\n<\/ul>\n\n\n\n<p class=\"has-text-align-center has-text-color has-background has-link-color has-large-font-size wp-elements-62dcce2f8788d0394fd237f3e0aff98b\" style=\"color:#000060;background-color:#dfc816\"><strong>Types of Chemical Formulas<\/strong>:<\/p>\n\n\n\n<ul class=\"has-large-font-size wp-block-list\">\n<li><strong>Empirical Formula<\/strong>: Represents the simplest whole-number ratio of elements in a compound (e.g., CH for benzene).<\/li>\n\n\n\n<li><strong>Molecular Formula<\/strong>: Represents the actual number of atoms of each element in a molecule (e.g., C6H6 for benzene).<\/li>\n\n\n\n<li><strong>Structural Formula<\/strong>: Shows the arrangement of atoms in a molecule.<\/li>\n<\/ul>\n\n\n\n<p class=\"has-text-align-center has-text-color has-background has-link-color has-large-font-size wp-elements-ad3ba524d1dc8cab79a19ef431003a24\" style=\"color:#000060;background-color:#dfc816\"><strong>Writing Formulae for Ionic Compounds<\/strong>:<\/p>\n\n\n\n<ul class=\"has-large-font-size wp-block-list\">\n<li>Ionic compounds are formed by the transfer of electrons between metals and non-metals.<\/li>\n\n\n\n<li>To write the formula:\n<ol class=\"wp-block-list\">\n<li>Write the symbol of the metal (cation) first.<\/li>\n\n\n\n<li>Write the symbol of the non-metal (anion) next.<\/li>\n\n\n\n<li>Balance the charges to ensure the compound is neutral (e.g., NaCl, MgO).<\/li>\n\n\n\n<li>Use subscripts to indicate the number of ions needed to balance the charges (e.g., Al\u2082O\u2083 for aluminum oxide).<\/li>\n<\/ol>\n<\/li>\n<\/ul>\n\n\n\n<p class=\"has-text-align-center has-text-color has-background has-link-color has-large-font-size wp-elements-1d2609644adc8e514b7e5f24ac6f6010\" style=\"color:#000060;background-color:#dfc816\"><strong>Writing Formulae for Covalent Compounds<\/strong>:<\/p>\n\n\n\n<ul class=\"has-large-font-size wp-block-list\">\n<li>Covalent compounds are formed by the sharing of electrons between non-metals.<\/li>\n\n\n\n<li>Use prefixes (mono-, di-, tri-, etc.) to indicate the number of atoms of each element (e.g., CO\u2082 for carbon dioxide, N\u2082O\u2084 for dinitrogen tetroxide).<\/li>\n\n\n\n<li>Do not use prefixes for the first element if it has only one atom (e.g., CO for carbon monoxide).<\/li>\n<\/ul>\n\n\n\n<p class=\"has-text-align-center has-text-color has-background has-link-color has-large-font-size wp-elements-394b38a80d95dfe78fcf3283c1eeeaf9\" style=\"color:#000060;background-color:#dfc816\"><strong>Polyatomic Ions<\/strong>:<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2024\/11\/image-65-1024x576.png\" alt=\"\" class=\"wp-image-16083\" style=\"width:439px;height:auto\" srcset=\"https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2024\/11\/image-65-1024x576.png 1024w, https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2024\/11\/image-65-300x169.png 300w, https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2024\/11\/image-65-768x432.png 768w, https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2024\/11\/image-65.png 1280w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure><\/div>\n\n\n<ul class=\"has-large-font-size wp-block-list\">\n<li>Some compounds contain polyatomic ions (groups of atoms that carry a charge), such as sulfate (SO\u2084\u00b2\u207b), nitrate (NO\u2083\u207b), and ammonium (NH\u2084\u207a).<\/li>\n\n\n\n<li>In these cases, the polyatomic ion is treated as a single unit and placed in parentheses if more than one is needed (e.g., Ca(NO\u2083)\u2082 for calcium nitrate).<\/li>\n<\/ul>\n\n\n\n<p class=\"has-text-align-center has-text-color has-background has-link-color has-large-font-size wp-elements-256296076170457eeb2e8ea15cf49884\" style=\"color:#000060;background-color:#dfc816\"><strong>Balancing the Charges<\/strong>:<\/p>\n\n\n\n<ul class=\"has-large-font-size wp-block-list\">\n<li>The total positive charge must equal the total negative charge to ensure the compound is neutral.<\/li>\n\n\n\n<li>The number of cations and anions can be adjusted by using appropriate subscripts.<\/li>\n<\/ul>\n\n\n\n<p class=\"has-text-align-center has-text-color has-background has-link-color has-large-font-size wp-elements-10e28679b5131db1b41a53771fa30e71\" style=\"color:#000060;background-color:#dfc816\"><strong>Common Examples<\/strong>:<\/p>\n\n\n\n<ul class=\"has-large-font-size wp-block-list\">\n<li>Sodium chloride: NaCl (1:1 ratio of Na+ and Cl-).<\/li>\n\n\n\n<li>Calcium carbonate: CaCO\u2083 (Ca\u00b2\u207a and CO\u2083\u00b2\u207b in a 1:1 ratio).<\/li>\n\n\n\n<li>Water: H\u2082O (two hydrogen atoms for every oxygen atom).<\/li>\n<\/ul>\n\n\n\n<p class=\"has-text-align-center has-text-color has-background has-link-color has-large-font-size wp-elements-4e92dc82a25d454cce4792b814229870\" style=\"color:#000060;background-color:#dfc816\"><strong>Rules for Writing Chemical Formulae<\/strong>:<\/p>\n\n\n\n<ul class=\"has-large-font-size wp-block-list\">\n<li><strong>For Ionic Compounds<\/strong>: Balance charges, write the cation first, and use the lowest ratio of ions.<\/li>\n\n\n\n<li><strong>For Covalent Compounds<\/strong>: Use prefixes to indicate the number of atoms of each element.<\/li>\n<\/ul>\n\n\n\n<p class=\"has-text-color has-large-font-size\" style=\"color:#d90000\">Let&#8217;s practice!<\/p>\n\n\n\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-9d6595d7 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><a href=\"https:\/\/wordwall.net\/play\/75922\/133\/211\"><img loading=\"lazy\" decoding=\"async\" width=\"500\" height=\"500\" src=\"https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2023\/03\/Worksheet-1-2-13.png\" alt=\"\" class=\"wp-image-6376\" srcset=\"https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2023\/03\/Worksheet-1-2-13.png 500w, https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2023\/03\/Worksheet-1-2-13-300x300.png 300w, https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2023\/03\/Worksheet-1-2-13-150x150.png 150w\" sizes=\"auto, (max-width: 500px) 100vw, 500px\" \/><\/a><\/figure>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full\"><a href=\"https:\/\/wordwall.net\/play\/58850\/702\/705\"><img loading=\"lazy\" decoding=\"async\" width=\"500\" height=\"500\" src=\"https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2023\/03\/Worksheet-1-1-1-14.png\" alt=\"\" class=\"wp-image-6377\" srcset=\"https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2023\/03\/Worksheet-1-1-1-14.png 500w, https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2023\/03\/Worksheet-1-1-1-14-300x300.png 300w, https:\/\/9thclass.deltapublications.in\/wp-content\/uploads\/2023\/03\/Worksheet-1-1-1-14-150x150.png 150w\" sizes=\"auto, (max-width: 500px) 100vw, 500px\" \/><\/a><\/figure>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Writing Chemical &nbsp;Formulae Key Notes: Definition of Chemical Formula: Symbols of Elements: Types of Chemical Formulas: Writing Formulae for Ionic Compounds: Writing Formulae for Covalent Compounds: Polyatomic Ions: Balancing the Charges: Common Examples: Rules for Writing Chemical Formulae: Let&#8217;s practice!<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"class_list":["post-3647","page","type-page","status-publish","hentry","entry"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/9thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages\/3647","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/9thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/9thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/9thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/9thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/comments?post=3647"}],"version-history":[{"count":19,"href":"https:\/\/9thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages\/3647\/revisions"}],"predecessor-version":[{"id":16338,"href":"https:\/\/9thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/pages\/3647\/revisions\/16338"}],"wp:attachment":[{"href":"https:\/\/9thclass.deltapublications.in\/index.php\/wp-json\/wp\/v2\/media?parent=3647"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}