{"id":90580,"date":"2025-06-01T10:31:24","date_gmt":"2025-06-01T10:31:24","guid":{"rendered":"https:\/\/exam.pscnotes.com\/mcq\/?p=90580"},"modified":"2025-06-01T10:31:24","modified_gmt":"2025-06-01T10:31:24","slug":"when-calcium-metal-reacts-with-sulphuric-acid-the-reaction-stops-afte","status":"publish","type":"post","link":"https:\/\/exam.pscnotes.com\/mcq\/when-calcium-metal-reacts-with-sulphuric-acid-the-reaction-stops-afte\/","title":{"rendered":"When calcium metal reacts with sulphuric acid, the reaction stops afte"},"content":{"rendered":"

When calcium metal reacts with sulphuric acid, the reaction stops after a short while. Why?<\/p>\n

[amp_mcq option1=”The reaction of calcium with sulphuric acid is not feasible at room temperature” option2=”Formed calcium sulphate is insoluble in water and covers the metal, preventing it from reacting any further” option3=”Formed calcium sulphate requires two molecules of water to crystallize as gypsum” option4=”Formed calcium sulphate is unstable” correct=”option2″]<\/p>\n

\n
\n
This question was previously asked in<\/div>\n
UPSC CAPF – 2021<\/div>\n<\/div>\n
Download PDF<\/a>Attempt Online<\/a><\/div>\n<\/div>\n
\nThe correct answer is B) Formed calcium sulphate is insoluble in water and covers the metal, preventing it from reacting any further.
\n<\/section>\n
\nCalcium is a relatively reactive metal that reacts with acids like sulfuric acid to produce hydrogen gas and a salt: Ca(s) + H\u2082SO\u2084(aq) \u2192 CaSO\u2084(s) + H\u2082(g). However, calcium sulfate (CaSO\u2084) is sparingly soluble in water, and its solubility is even lower in concentrated sulfuric acid. As the reaction proceeds, a layer of solid calcium sulfate forms on the surface of the calcium metal. This layer acts as a barrier, preventing the sulfuric acid from coming into contact with the underlying calcium metal, effectively stopping or significantly slowing down the reaction after a short while. This phenomenon is known as passivation.
\n<\/section>\n
\nOther metals that exhibit passivation with sulfuric acid include lead (forming insoluble PbSO\u2084) and barium (forming insoluble BaSO\u2084). With other acids like hydrochloric acid, calcium reacts vigorously because calcium chloride (CaCl\u2082) is soluble.
\n<\/section>\n","protected":false},"excerpt":{"rendered":"

When calcium metal reacts with sulphuric acid, the reaction stops after a short while. Why? [amp_mcq option1=”The reaction of calcium with sulphuric acid is not feasible at room temperature” option2=”Formed calcium sulphate is insoluble in water and covers the metal, preventing it from reacting any further” option3=”Formed calcium sulphate requires two molecules of water to … <\/p>\n

Detailed SolutionWhen calcium metal reacts with sulphuric acid, the reaction stops afte<\/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":[1085],"tags":[1110,1096,1109],"class_list":["post-90580","post","type-post","status-publish","format-standard","hentry","category-upsc-capf","tag-1110","tag-chemistry","tag-metals-minerals-ores-properties-uses","no-featured-image-padding"],"yoast_head":"\nWhen calcium metal reacts with sulphuric acid, the reaction stops afte<\/title>\n<meta name=\"description\" content=\"The correct answer is B) Formed calcium sulphate is insoluble in water and covers the metal, preventing it from reacting any further. Calcium is a relatively reactive metal that reacts with acids like sulfuric acid to produce hydrogen gas and a salt: Ca(s) + H\u2082SO\u2084(aq) \u2192 CaSO\u2084(s) + H\u2082(g). However, calcium sulfate (CaSO\u2084) is sparingly soluble in water, and its solubility is even lower in concentrated sulfuric acid. As the reaction proceeds, a layer of solid calcium sulfate forms on the surface of the calcium metal. This layer acts as a barrier, preventing the sulfuric acid from coming into contact with the underlying calcium metal, effectively stopping or significantly slowing down the reaction after a short while. This phenomenon is known as passivation.\" \/>\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\/when-calcium-metal-reacts-with-sulphuric-acid-the-reaction-stops-afte\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"When calcium metal reacts with sulphuric acid, the reaction stops afte\" \/>\n<meta property=\"og:description\" content=\"The correct answer is B) Formed calcium sulphate is insoluble in water and covers the metal, preventing it from reacting any further. Calcium is a relatively reactive metal that reacts with acids like sulfuric acid to produce hydrogen gas and a salt: Ca(s) + H\u2082SO\u2084(aq) \u2192 CaSO\u2084(s) + H\u2082(g). However, calcium sulfate (CaSO\u2084) is sparingly soluble in water, and its solubility is even lower in concentrated sulfuric acid. As the reaction proceeds, a layer of solid calcium sulfate forms on the surface of the calcium metal. This layer acts as a barrier, preventing the sulfuric acid from coming into contact with the underlying calcium metal, effectively stopping or significantly slowing down the reaction after a short while. This phenomenon is known as passivation.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/exam.pscnotes.com\/mcq\/when-calcium-metal-reacts-with-sulphuric-acid-the-reaction-stops-afte\/\" \/>\n<meta property=\"og:site_name\" content=\"MCQ and Quiz for Exams\" \/>\n<meta property=\"article:published_time\" content=\"2025-06-01T10:31:24+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":"When calcium metal reacts with sulphuric acid, the reaction stops afte","description":"The correct answer is B) Formed calcium sulphate is insoluble in water and covers the metal, preventing it from reacting any further. Calcium is a relatively reactive metal that reacts with acids like sulfuric acid to produce hydrogen gas and a salt: Ca(s) + H\u2082SO\u2084(aq) \u2192 CaSO\u2084(s) + H\u2082(g). However, calcium sulfate (CaSO\u2084) is sparingly soluble in water, and its solubility is even lower in concentrated sulfuric acid. As the reaction proceeds, a layer of solid calcium sulfate forms on the surface of the calcium metal. This layer acts as a barrier, preventing the sulfuric acid from coming into contact with the underlying calcium metal, effectively stopping or significantly slowing down the reaction after a short while. This phenomenon is known as passivation.","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\/when-calcium-metal-reacts-with-sulphuric-acid-the-reaction-stops-afte\/","og_locale":"en_US","og_type":"article","og_title":"When calcium metal reacts with sulphuric acid, the reaction stops afte","og_description":"The correct answer is B) Formed calcium sulphate is insoluble in water and covers the metal, preventing it from reacting any further. Calcium is a relatively reactive metal that reacts with acids like sulfuric acid to produce hydrogen gas and a salt: Ca(s) + H\u2082SO\u2084(aq) \u2192 CaSO\u2084(s) + H\u2082(g). However, calcium sulfate (CaSO\u2084) is sparingly soluble in water, and its solubility is even lower in concentrated sulfuric acid. As the reaction proceeds, a layer of solid calcium sulfate forms on the surface of the calcium metal. This layer acts as a barrier, preventing the sulfuric acid from coming into contact with the underlying calcium metal, effectively stopping or significantly slowing down the reaction after a short while. This phenomenon is known as passivation.","og_url":"https:\/\/exam.pscnotes.com\/mcq\/when-calcium-metal-reacts-with-sulphuric-acid-the-reaction-stops-afte\/","og_site_name":"MCQ and Quiz for Exams","article_published_time":"2025-06-01T10:31:24+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\/when-calcium-metal-reacts-with-sulphuric-acid-the-reaction-stops-afte\/","url":"https:\/\/exam.pscnotes.com\/mcq\/when-calcium-metal-reacts-with-sulphuric-acid-the-reaction-stops-afte\/","name":"When calcium metal reacts with sulphuric acid, the reaction stops afte","isPartOf":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/#website"},"datePublished":"2025-06-01T10:31:24+00:00","dateModified":"2025-06-01T10:31:24+00:00","author":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/#\/schema\/person\/5807dafeb27d2ec82344d6cbd6c3d209"},"description":"The correct answer is B) Formed calcium sulphate is insoluble in water and covers the metal, preventing it from reacting any further. Calcium is a relatively reactive metal that reacts with acids like sulfuric acid to produce hydrogen gas and a salt: Ca(s) + H\u2082SO\u2084(aq) \u2192 CaSO\u2084(s) + H\u2082(g). However, calcium sulfate (CaSO\u2084) is sparingly soluble in water, and its solubility is even lower in concentrated sulfuric acid. As the reaction proceeds, a layer of solid calcium sulfate forms on the surface of the calcium metal. This layer acts as a barrier, preventing the sulfuric acid from coming into contact with the underlying calcium metal, effectively stopping or significantly slowing down the reaction after a short while. This phenomenon is known as passivation.","breadcrumb":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/when-calcium-metal-reacts-with-sulphuric-acid-the-reaction-stops-afte\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/exam.pscnotes.com\/mcq\/when-calcium-metal-reacts-with-sulphuric-acid-the-reaction-stops-afte\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/exam.pscnotes.com\/mcq\/when-calcium-metal-reacts-with-sulphuric-acid-the-reaction-stops-afte\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/exam.pscnotes.com\/mcq\/"},{"@type":"ListItem","position":2,"name":"UPSC CAPF","item":"https:\/\/exam.pscnotes.com\/mcq\/category\/upsc-capf\/"},{"@type":"ListItem","position":3,"name":"When calcium metal reacts with sulphuric acid, the reaction stops afte"}]},{"@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\/90580","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=90580"}],"version-history":[{"count":0,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/posts\/90580\/revisions"}],"wp:attachment":[{"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/media?parent=90580"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/categories?post=90580"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/exam.pscnotes.com\/mcq\/wp-json\/wp\/v2\/tags?post=90580"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}