Why does CdS dissolve in HCl, when CuS and Bi2S3 will not?<\/p>\n\n\n\n
The Correct Answer and Explanation is :<\/strong><\/mark><\/p>\n\n\n\n The differing solubility of CdS, CuS, and Bi\u2082S\u2083 in HCl can be explained by their distinct chemical properties, solubility products (Ksp), and interactions with acids.<\/p>\n\n\n\n CdS dissolves in HCl because it reacts with the acid to form soluble cadmium chloride (CdCl\u2082) and releases H\u2082S gas. CuS and Bi\u2082S\u2083, however, have much lower solubility products (Ksp) and do not react significantly with HCl under similar conditions.<\/p>\n\n\n\n The solubility of metal sulfides in HCl depends on their Ksp values<\/strong> and the extent to which they can react with the acid. CdS, CuS, and Bi\u2082S\u2083 are all sulfides of transition metals, but their reactivity with HCl varies significantly:<\/p>\n\n\n\n Thus, the dissolution of CdS in HCl is a result of its moderate solubility, weaker metal-sulfur bonds, and the favorable reaction that forms soluble products and gaseous H\u2082S, unlike CuS and Bi\u2082S\u2083.<\/p>\n","protected":false},"excerpt":{"rendered":" Why does CdS dissolve in HCl, when CuS and Bi2S3 will not? The Correct Answer and Explanation is : The differing solubility of CdS, CuS, and Bi\u2082S\u2083 in HCl can be explained by their distinct chemical properties, solubility products (Ksp), and interactions with acids. Correct Answer: CdS dissolves in HCl because it reacts with the […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-184784","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/184784","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=184784"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/184784\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=184784"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=184784"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=184784"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Correct Answer:<\/h3>\n\n\n\n
Explanation (300 words):<\/h3>\n\n\n\n
\n
CdS is a moderately soluble sulfide compared to CuS and Bi\u2082S\u2083. In the presence of HCl, CdS reacts as follows:
[
\\text{CdS (s) + 2 HCl (aq)} \\rightarrow \\text{CdCl}_2 \\text{(aq) + H}_2\\text{S (g)}.
]
The formation of the soluble salt CdCl\u2082 and the removal of H\u2082S gas drive the reaction forward, allowing CdS to dissolve readily in HCl.<\/li>\n\n\n\n
CuS and Bi\u2082S\u2083 have significantly lower Ksp values, making them less soluble. CuS, for instance, forms strong Cu-S bonds that resist reaction with HCl. Similarly, Bi\u2082S\u2083 has a highly stable lattice structure and is not easily attacked by H\u207a ions. These compounds are more resistant to protonation and thus remain insoluble in HCl.<\/li>\n\n\n\n
The solubility of metal sulfides is influenced by the hydrolysis of the sulfide ion (S\u00b2\u207b). CdS is more prone to release S\u00b2\u207b into solution, which then reacts with H\u207a from HCl to form H\u2082S gas. In contrast, CuS and Bi\u2082S\u2083 do not release sufficient sulfide ions to sustain the reaction with HCl.<\/li>\n<\/ol>\n\n\n\n