{"id":92799,"date":"2025-06-01T11:32:49","date_gmt":"2025-06-01T11:32:49","guid":{"rendered":"https:\/\/exam.pscnotes.com\/mcq\/?p=92799"},"modified":"2025-06-01T11:32:49","modified_gmt":"2025-06-01T11:32:49","slug":"an-element-has-an-atomic-number-of-16-what-is-the-principal-quantum-n","status":"publish","type":"post","link":"https:\/\/exam.pscnotes.com\/mcq\/an-element-has-an-atomic-number-of-16-what-is-the-principal-quantum-n\/","title":{"rendered":"An element has an atomic number of 16. What is the principal quantum n"},"content":{"rendered":"

An element has an atomic number of 16. What is the principal quantum number (n) of its outermost electrons ?<\/p>\n

[amp_mcq option1=”1″ option2=”2″ option3=”3″ option4=”4″ correct=”option3″]<\/p>\n

\n
\n
This question was previously asked in<\/div>\n
UPSC CISF-AC-EXE – 2020<\/div>\n<\/div>\n
Download PDF<\/a>Attempt Online<\/a><\/div>\n<\/div>\n
\nAn element with atomic number 16 is Sulfur (S). To find the principal quantum number (n) of its outermost electrons, we need to write its electron configuration. The atomic number represents the number of protons and, in a neutral atom, the number of electrons. So, Sulfur has 16 electrons. The electron configuration is filled according to the Aufbau principle, Hund’s rule, and the Pauli exclusion principle.
\nFilling order: 1s, 2s, 2p, 3s, 3p, 4s, 3d, …
\nElectrons:
\n1s\u00b2 (2 electrons)
\n2s\u00b2 (2 electrons)
\n2p\u2076 (6 electrons) – total 2+2+6 = 10 electrons
\n3s\u00b2 (2 electrons) – total 10+2 = 12 electrons
\n3p\u2074 (4 electrons) – total 12+4 = 16 electrons
\nThe electron configuration is 1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 3p\u2074. The outermost electrons are those in the highest principal energy level, which is n=3 in this case (3s and 3p orbitals).
\n<\/section>\n
\nThe principal quantum number (n) of the outermost electrons corresponds to the highest energy level occupied by electrons in the atom’s electron configuration. For Sulfur (atomic number 16), the configuration is 1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 3p\u2074, so the outermost electrons are in the n=3 level.
\n<\/section>\n
\nThe outer electron shell is often referred to as the valence shell. The principal quantum number ‘n’ defines the energy level and size of the electron shell. n=1 is the first shell, n=2 is the second shell, n=3 is the third shell, and so on.
\n<\/section>\n","protected":false},"excerpt":{"rendered":"

An element has an atomic number of 16. What is the principal quantum number (n) of its outermost electrons ? [amp_mcq option1=”1″ option2=”2″ option3=”3″ option4=”4″ correct=”option3″] This question was previously asked in UPSC CISF-AC-EXE – 2020 Download PDFAttempt Online An element with atomic number 16 is Sulfur (S). To find the principal quantum number (n) … <\/p>\n

Detailed SolutionAn element has an atomic number of 16. What is the principal quantum n<\/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":[1288,1162,1096],"class_list":["post-92799","post","type-post","status-publish","format-standard","hentry","category-upsc-cisf-ac-exe","tag-1288","tag-atomic-structure","tag-chemistry","no-featured-image-padding"],"yoast_head":"\nAn element has an atomic number of 16. What is the principal quantum n<\/title>\n<meta name=\"description\" content=\"An element with atomic number 16 is Sulfur (S). To find the principal quantum number (n) of its outermost electrons, we need to write its electron configuration. The atomic number represents the number of protons and, in a neutral atom, the number of electrons. So, Sulfur has 16 electrons. The electron configuration is filled according to the Aufbau principle, Hund's rule, and the Pauli exclusion principle. Filling order: 1s, 2s, 2p, 3s, 3p, 4s, 3d, ... Electrons: 1s\u00b2 (2 electrons) 2s\u00b2 (2 electrons) 2p\u2076 (6 electrons) - total 2+2+6 = 10 electrons 3s\u00b2 (2 electrons) - total 10+2 = 12 electrons 3p\u2074 (4 electrons) - total 12+4 = 16 electrons The electron configuration is 1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 3p\u2074. The outermost electrons are those in the highest principal energy level, which is n=3 in this case (3s and 3p orbitals). The principal quantum number (n) of the outermost electrons corresponds to the highest energy level occupied by electrons in the atom's electron configuration. For Sulfur (atomic number 16), the configuration is 1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 3p\u2074, so the outermost electrons are in the n=3 level.\" \/>\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\/an-element-has-an-atomic-number-of-16-what-is-the-principal-quantum-n\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"An element has an atomic number of 16. What is the principal quantum n\" \/>\n<meta property=\"og:description\" content=\"An element with atomic number 16 is Sulfur (S). To find the principal quantum number (n) of its outermost electrons, we need to write its electron configuration. The atomic number represents the number of protons and, in a neutral atom, the number of electrons. So, Sulfur has 16 electrons. The electron configuration is filled according to the Aufbau principle, Hund's rule, and the Pauli exclusion principle. Filling order: 1s, 2s, 2p, 3s, 3p, 4s, 3d, ... Electrons: 1s\u00b2 (2 electrons) 2s\u00b2 (2 electrons) 2p\u2076 (6 electrons) - total 2+2+6 = 10 electrons 3s\u00b2 (2 electrons) - total 10+2 = 12 electrons 3p\u2074 (4 electrons) - total 12+4 = 16 electrons The electron configuration is 1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 3p\u2074. The outermost electrons are those in the highest principal energy level, which is n=3 in this case (3s and 3p orbitals). The principal quantum number (n) of the outermost electrons corresponds to the highest energy level occupied by electrons in the atom's electron configuration. For Sulfur (atomic number 16), the configuration is 1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 3p\u2074, so the outermost electrons are in the n=3 level.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/exam.pscnotes.com\/mcq\/an-element-has-an-atomic-number-of-16-what-is-the-principal-quantum-n\/\" \/>\n<meta property=\"og:site_name\" content=\"MCQ and Quiz for Exams\" \/>\n<meta property=\"article:published_time\" content=\"2025-06-01T11:32:49+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=\"1 minute\" \/>\n<!-- \/ Yoast SEO Premium plugin. -->","yoast_head_json":{"title":"An element has an atomic number of 16. What is the principal quantum n","description":"An element with atomic number 16 is Sulfur (S). To find the principal quantum number (n) of its outermost electrons, we need to write its electron configuration. The atomic number represents the number of protons and, in a neutral atom, the number of electrons. So, Sulfur has 16 electrons. The electron configuration is filled according to the Aufbau principle, Hund's rule, and the Pauli exclusion principle. Filling order: 1s, 2s, 2p, 3s, 3p, 4s, 3d, ... Electrons: 1s\u00b2 (2 electrons) 2s\u00b2 (2 electrons) 2p\u2076 (6 electrons) - total 2+2+6 = 10 electrons 3s\u00b2 (2 electrons) - total 10+2 = 12 electrons 3p\u2074 (4 electrons) - total 12+4 = 16 electrons The electron configuration is 1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 3p\u2074. The outermost electrons are those in the highest principal energy level, which is n=3 in this case (3s and 3p orbitals). The principal quantum number (n) of the outermost electrons corresponds to the highest energy level occupied by electrons in the atom's electron configuration. For Sulfur (atomic number 16), the configuration is 1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 3p\u2074, so the outermost electrons are in the n=3 level.","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\/an-element-has-an-atomic-number-of-16-what-is-the-principal-quantum-n\/","og_locale":"en_US","og_type":"article","og_title":"An element has an atomic number of 16. What is the principal quantum n","og_description":"An element with atomic number 16 is Sulfur (S). To find the principal quantum number (n) of its outermost electrons, we need to write its electron configuration. The atomic number represents the number of protons and, in a neutral atom, the number of electrons. So, Sulfur has 16 electrons. The electron configuration is filled according to the Aufbau principle, Hund's rule, and the Pauli exclusion principle. Filling order: 1s, 2s, 2p, 3s, 3p, 4s, 3d, ... Electrons: 1s\u00b2 (2 electrons) 2s\u00b2 (2 electrons) 2p\u2076 (6 electrons) - total 2+2+6 = 10 electrons 3s\u00b2 (2 electrons) - total 10+2 = 12 electrons 3p\u2074 (4 electrons) - total 12+4 = 16 electrons The electron configuration is 1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 3p\u2074. The outermost electrons are those in the highest principal energy level, which is n=3 in this case (3s and 3p orbitals). The principal quantum number (n) of the outermost electrons corresponds to the highest energy level occupied by electrons in the atom's electron configuration. For Sulfur (atomic number 16), the configuration is 1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 3p\u2074, so the outermost electrons are in the n=3 level.","og_url":"https:\/\/exam.pscnotes.com\/mcq\/an-element-has-an-atomic-number-of-16-what-is-the-principal-quantum-n\/","og_site_name":"MCQ and Quiz for Exams","article_published_time":"2025-06-01T11:32:49+00:00","author":"rawan239","twitter_card":"summary_large_image","twitter_misc":{"Written by":"rawan239","Est. reading time":"1 minute"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/exam.pscnotes.com\/mcq\/an-element-has-an-atomic-number-of-16-what-is-the-principal-quantum-n\/","url":"https:\/\/exam.pscnotes.com\/mcq\/an-element-has-an-atomic-number-of-16-what-is-the-principal-quantum-n\/","name":"An element has an atomic number of 16. What is the principal quantum n","isPartOf":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/#website"},"datePublished":"2025-06-01T11:32:49+00:00","dateModified":"2025-06-01T11:32:49+00:00","author":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/#\/schema\/person\/5807dafeb27d2ec82344d6cbd6c3d209"},"description":"An element with atomic number 16 is Sulfur (S). To find the principal quantum number (n) of its outermost electrons, we need to write its electron configuration. The atomic number represents the number of protons and, in a neutral atom, the number of electrons. So, Sulfur has 16 electrons. The electron configuration is filled according to the Aufbau principle, Hund's rule, and the Pauli exclusion principle. Filling order: 1s, 2s, 2p, 3s, 3p, 4s, 3d, ... Electrons: 1s\u00b2 (2 electrons) 2s\u00b2 (2 electrons) 2p\u2076 (6 electrons) - total 2+2+6 = 10 electrons 3s\u00b2 (2 electrons) - total 10+2 = 12 electrons 3p\u2074 (4 electrons) - total 12+4 = 16 electrons The electron configuration is 1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 3p\u2074. The outermost electrons are those in the highest principal energy level, which is n=3 in this case (3s and 3p orbitals). The principal quantum number (n) of the outermost electrons corresponds to the highest energy level occupied by electrons in the atom's electron configuration. For Sulfur (atomic number 16), the configuration is 1s\u00b2 2s\u00b2 2p\u2076 3s\u00b2 3p\u2074, so the outermost electrons are in the n=3 level.","breadcrumb":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/an-element-has-an-atomic-number-of-16-what-is-the-principal-quantum-n\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/exam.pscnotes.com\/mcq\/an-element-has-an-atomic-number-of-16-what-is-the-principal-quantum-n\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/exam.pscnotes.com\/mcq\/an-element-has-an-atomic-number-of-16-what-is-the-principal-quantum-n\/#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":"An element has an atomic number of 16. 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