{"id":92648,"date":"2025-06-01T11:29:50","date_gmt":"2025-06-01T11:29:50","guid":{"rendered":"https:\/\/exam.pscnotes.com\/mcq\/?p=92648"},"modified":"2025-06-01T11:29:50","modified_gmt":"2025-06-01T11:29:50","slug":"which-one-of-the-following-elements-forms-compounds-with-pronounced-co","status":"publish","type":"post","link":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-elements-forms-compounds-with-pronounced-co\/","title":{"rendered":"Which one of the following elements forms compounds with pronounced co"},"content":{"rendered":"

Which one of the following elements forms compounds with pronounced covalent character?<\/p>\n

[amp_mcq option1=”Lithium (Li)” option2=”Sodium (Na)” option3=”Potassium (K)” option4=”Rubidium (Rb)” correct=”option1″]<\/p>\n

\n
\n
This question was previously asked in<\/div>\n
UPSC CISF-AC-EXE – 2019<\/div>\n<\/div>\n
Download PDF<\/a>Attempt Online<\/a><\/div>\n<\/div>\n
\nLithium (Li) forms compounds with the most pronounced covalent character among the given options.
\n<\/section>\n
\nThe formation of covalent character in predominantly ionic compounds is explained by Fajans’ Rules. These rules state that a compound is more likely to have covalent character if:
\n1. The cation is small.
\n2. The cation has a high charge (not applicable here as all form +1 ions).
\n3. The anion is large (not directly comparable here as the anion is not specified, but assume it’s a common one like a halide).
\n4. The cation has a pseudo noble gas configuration (not applicable here as alkali metals form noble gas configuration ions).<\/p>\n

The given elements are alkali metals: Lithium (Li), Sodium (Na), Potassium (K), and Rubidium (Rb). When they form compounds, they form +1 ions: Li\u207a, Na\u207a, K\u207a, Rb\u207a.
\nTheir ionic radii increase down the group: Li\u207a < Na\u207a < K\u207a < Rb\u207a.\n\nAccording to Fajans' Rules, smaller cations have higher polarizing power (the ability to distort the electron cloud of the anion), which leads to increased covalent character in the bond.\nLi\u207a is the smallest cation among Li\u207a, Na\u207a, K\u207a, and Rb\u207a. Therefore, Li\u207a has the highest polarizing power and forms compounds with anions that exhibit the most pronounced covalent character compared to the compounds of Na, K, and Rb with the same anion.\nFor example, LiCl has significantly more covalent character than NaCl, KCl, or RbCl.\n<\/section>\n

\nLithium exhibits several properties that are anomalous compared to the other alkali metals, often showing similarities to magnesium (diagonal relationship). This pronounced covalent character is one such anomaly, explaining why compounds like LiCl are soluble in organic solvents and why Li\u2082CO\u2083 is less stable to heat than other alkali metal carbonates.
\n<\/section>\n","protected":false},"excerpt":{"rendered":"

Which one of the following elements forms compounds with pronounced covalent character? [amp_mcq option1=”Lithium (Li)” option2=”Sodium (Na)” option3=”Potassium (K)” option4=”Rubidium (Rb)” correct=”option1″] This question was previously asked in UPSC CISF-AC-EXE – 2019 Download PDFAttempt Online Lithium (Li) forms compounds with the most pronounced covalent character among the given options. The formation of covalent character in … <\/p>\n

Detailed SolutionWhich one of the following elements forms compounds with pronounced co<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1089],"tags":[1119,1096,1239],"class_list":["post-92648","post","type-post","status-publish","format-standard","hentry","category-upsc-cisf-ac-exe","tag-1119","tag-chemistry","tag-inorganic-chemistry","no-featured-image-padding"],"yoast_head":"\nWhich one of the following elements forms compounds with pronounced co<\/title>\n<meta name=\"description\" content=\"Lithium (Li) forms compounds with the most pronounced covalent character among the given options. The formation of covalent character in predominantly ionic compounds is explained by Fajans' Rules. These rules state that a compound is more likely to have covalent character if: 1. The cation is small. 2. The cation has a high charge (not applicable here as all form +1 ions). 3. The anion is large (not directly comparable here as the anion is not specified, but assume it's a common one like a halide). 4. The cation has a pseudo noble gas configuration (not applicable here as alkali metals form noble gas configuration ions). The given elements are alkali metals: Lithium (Li), Sodium (Na), Potassium (K), and Rubidium (Rb). When they form compounds, they form +1 ions: Li\u207a, Na\u207a, K\u207a, Rb\u207a. Their ionic radii increase down the group: Li\u207a < Na\u207a < K\u207a < Rb\u207a. According to Fajans' Rules, smaller cations have higher polarizing power (the ability to distort the electron cloud of the anion), which leads to increased covalent character in the bond. Li\u207a is the smallest cation among Li\u207a, Na\u207a, K\u207a, and Rb\u207a. Therefore, Li\u207a has the highest polarizing power and forms compounds with anions that exhibit the most pronounced covalent character compared to the compounds of Na, K, and Rb with the same anion. For example, LiCl has significantly more covalent character than NaCl, KCl, or RbCl.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-elements-forms-compounds-with-pronounced-co\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Which one of the following elements forms compounds with pronounced co\" \/>\n<meta property=\"og:description\" content=\"Lithium (Li) forms compounds with the most pronounced covalent character among the given options. The formation of covalent character in predominantly ionic compounds is explained by Fajans' Rules. These rules state that a compound is more likely to have covalent character if: 1. The cation is small. 2. The cation has a high charge (not applicable here as all form +1 ions). 3. The anion is large (not directly comparable here as the anion is not specified, but assume it's a common one like a halide). 4. The cation has a pseudo noble gas configuration (not applicable here as alkali metals form noble gas configuration ions). The given elements are alkali metals: Lithium (Li), Sodium (Na), Potassium (K), and Rubidium (Rb). When they form compounds, they form +1 ions: Li\u207a, Na\u207a, K\u207a, Rb\u207a. Their ionic radii increase down the group: Li\u207a < Na\u207a < K\u207a < Rb\u207a. According to Fajans' Rules, smaller cations have higher polarizing power (the ability to distort the electron cloud of the anion), which leads to increased covalent character in the bond. Li\u207a is the smallest cation among Li\u207a, Na\u207a, K\u207a, and Rb\u207a. Therefore, Li\u207a has the highest polarizing power and forms compounds with anions that exhibit the most pronounced covalent character compared to the compounds of Na, K, and Rb with the same anion. For example, LiCl has significantly more covalent character than NaCl, KCl, or RbCl.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-elements-forms-compounds-with-pronounced-co\/\" \/>\n<meta property=\"og:site_name\" content=\"MCQ and Quiz for Exams\" \/>\n<meta property=\"article:published_time\" content=\"2025-06-01T11:29:50+00:00\" \/>\n<meta name=\"author\" content=\"rawan239\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"rawan239\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"2 minutes\" \/>\n<!-- \/ Yoast SEO Premium plugin. -->","yoast_head_json":{"title":"Which one of the following elements forms compounds with pronounced co","description":"Lithium (Li) forms compounds with the most pronounced covalent character among the given options. The formation of covalent character in predominantly ionic compounds is explained by Fajans' Rules. These rules state that a compound is more likely to have covalent character if: 1. The cation is small. 2. The cation has a high charge (not applicable here as all form +1 ions). 3. The anion is large (not directly comparable here as the anion is not specified, but assume it's a common one like a halide). 4. The cation has a pseudo noble gas configuration (not applicable here as alkali metals form noble gas configuration ions). The given elements are alkali metals: Lithium (Li), Sodium (Na), Potassium (K), and Rubidium (Rb). When they form compounds, they form +1 ions: Li\u207a, Na\u207a, K\u207a, Rb\u207a. Their ionic radii increase down the group: Li\u207a < Na\u207a < K\u207a < Rb\u207a. According to Fajans' Rules, smaller cations have higher polarizing power (the ability to distort the electron cloud of the anion), which leads to increased covalent character in the bond. Li\u207a is the smallest cation among Li\u207a, Na\u207a, K\u207a, and Rb\u207a. Therefore, Li\u207a has the highest polarizing power and forms compounds with anions that exhibit the most pronounced covalent character compared to the compounds of Na, K, and Rb with the same anion. For example, LiCl has significantly more covalent character than NaCl, KCl, or RbCl.","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-elements-forms-compounds-with-pronounced-co\/","og_locale":"en_US","og_type":"article","og_title":"Which one of the following elements forms compounds with pronounced co","og_description":"Lithium (Li) forms compounds with the most pronounced covalent character among the given options. The formation of covalent character in predominantly ionic compounds is explained by Fajans' Rules. These rules state that a compound is more likely to have covalent character if: 1. The cation is small. 2. The cation has a high charge (not applicable here as all form +1 ions). 3. The anion is large (not directly comparable here as the anion is not specified, but assume it's a common one like a halide). 4. The cation has a pseudo noble gas configuration (not applicable here as alkali metals form noble gas configuration ions). The given elements are alkali metals: Lithium (Li), Sodium (Na), Potassium (K), and Rubidium (Rb). When they form compounds, they form +1 ions: Li\u207a, Na\u207a, K\u207a, Rb\u207a. Their ionic radii increase down the group: Li\u207a < Na\u207a < K\u207a < Rb\u207a. According to Fajans' Rules, smaller cations have higher polarizing power (the ability to distort the electron cloud of the anion), which leads to increased covalent character in the bond. Li\u207a is the smallest cation among Li\u207a, Na\u207a, K\u207a, and Rb\u207a. Therefore, Li\u207a has the highest polarizing power and forms compounds with anions that exhibit the most pronounced covalent character compared to the compounds of Na, K, and Rb with the same anion. For example, LiCl has significantly more covalent character than NaCl, KCl, or RbCl.","og_url":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-elements-forms-compounds-with-pronounced-co\/","og_site_name":"MCQ and Quiz for Exams","article_published_time":"2025-06-01T11:29:50+00:00","author":"rawan239","twitter_card":"summary_large_image","twitter_misc":{"Written by":"rawan239","Est. reading time":"2 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-elements-forms-compounds-with-pronounced-co\/","url":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-elements-forms-compounds-with-pronounced-co\/","name":"Which one of the following elements forms compounds with pronounced co","isPartOf":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/#website"},"datePublished":"2025-06-01T11:29:50+00:00","dateModified":"2025-06-01T11:29:50+00:00","author":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/#\/schema\/person\/5807dafeb27d2ec82344d6cbd6c3d209"},"description":"Lithium (Li) forms compounds with the most pronounced covalent character among the given options. The formation of covalent character in predominantly ionic compounds is explained by Fajans' Rules. These rules state that a compound is more likely to have covalent character if: 1. The cation is small. 2. The cation has a high charge (not applicable here as all form +1 ions). 3. The anion is large (not directly comparable here as the anion is not specified, but assume it's a common one like a halide). 4. The cation has a pseudo noble gas configuration (not applicable here as alkali metals form noble gas configuration ions). The given elements are alkali metals: Lithium (Li), Sodium (Na), Potassium (K), and Rubidium (Rb). When they form compounds, they form +1 ions: Li\u207a, Na\u207a, K\u207a, Rb\u207a. Their ionic radii increase down the group: Li\u207a < Na\u207a < K\u207a < Rb\u207a. According to Fajans' Rules, smaller cations have higher polarizing power (the ability to distort the electron cloud of the anion), which leads to increased covalent character in the bond. Li\u207a is the smallest cation among Li\u207a, Na\u207a, K\u207a, and Rb\u207a. Therefore, Li\u207a has the highest polarizing power and forms compounds with anions that exhibit the most pronounced covalent character compared to the compounds of Na, K, and Rb with the same anion. For example, LiCl has significantly more covalent character than NaCl, KCl, or RbCl.","breadcrumb":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-elements-forms-compounds-with-pronounced-co\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-elements-forms-compounds-with-pronounced-co\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-elements-forms-compounds-with-pronounced-co\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/exam.pscnotes.com\/mcq\/"},{"@type":"ListItem","position":2,"name":"UPSC CISF-AC-EXE","item":"https:\/\/exam.pscnotes.com\/mcq\/category\/upsc-cisf-ac-exe\/"},{"@type":"ListItem","position":3,"name":"Which one of the following elements forms compounds with pronounced co"}]},{"@type":"WebSite","@id":"https:\/\/exam.pscnotes.com\/mcq\/#website","url":"https:\/\/exam.pscnotes.com\/mcq\/","name":"MCQ and Quiz for Exams","description":"","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/exam.pscnotes.com\/mcq\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"en-US"},{"@type":"Person","@id":"https:\/\/exam.pscnotes.com\/mcq\/#\/schema\/person\/5807dafeb27d2ec82344d6cbd6c3d209","name":"rawan239","image":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/exam.pscnotes.com\/mcq\/#\/schema\/person\/image\/","url":"https:\/\/secure.gravatar.com\/avatar\/761a7274f9cce048fa5b921221e7934820d74514df93ef195a9d22af0c1c9001?s=96&d=mm&r=g","contentUrl":"https:\/\/secure.gravatar.com\/avatar\/761a7274f9cce048fa5b921221e7934820d74514df93ef195a9d22af0c1c9001?s=96&d=mm&r=g","caption":"rawan239"},"sameAs":["https:\/\/exam.pscnotes.com"],"url":"https:\/\/exam.pscnotes.com\/mcq\/author\/rawan239\/"}]}},"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/posts\/92648","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/comments?post=92648"}],"version-history":[{"count":0,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/posts\/92648\/revisions"}],"wp:attachment":[{"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/media?parent=92648"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/categories?post=92648"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/tags?post=92648"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}