The correct answer is: B. 2Mg + O\u2082<\/strong><\/p>\n\n\n\n To predict the missing component in a chemical reaction, we analyze the reactants and products<\/strong> and use chemical balancing<\/strong> and reaction types<\/strong> (such as synthesis, decomposition, single replacement, or combustion).<\/p>\n\n\n\n Let’s examine the two given reactions:<\/p>\n\n\n\n Now, let\u2019s look at the multiple-choice options to find the missing component that can logically fit into this context:<\/p>\n\n\n\n Therefore, the correct prediction of the missing component that fits this context is:<\/p>\n\n\n\n This completes the reaction cycle, showing how magnesium forms MgO and how MgO can decompose back into its elements.<\/p>\n\n\n\n Predict the missing component of each reaction. MgO + H2O \u00e2\u2020\u2019 Mg(OH)2 2MgO \u00e2\u2020\u2019 2Mg + O2 A. 2Mg + H2O B. 2Mg + O2 C. MgOH + O2 D. MgO + O2 The Correct Answer and Explanation is: The correct answer is: B. 2Mg + O\u2082 Explanation To predict the missing component in a […]<\/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-226419","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/226419","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=226419"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/226419\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=226419"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=226419"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=226419"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
\n\n\n\nExplanation<\/h3>\n\n\n\n
\n
This is a synthesis reaction<\/strong> (also called a combination reaction), where a metal oxide reacts with water to form a metal hydroxide<\/strong>.
Magnesium oxide (MgO) is a basic oxide<\/strong>, and when it reacts with water, it forms magnesium hydroxide<\/strong>, Mg(OH)\u2082.
This equation is already complete and balanced.<\/li>\n\n\n\n
This is a decomposition reaction<\/strong>, where a compound breaks down into simpler substances.
Here, magnesium oxide decomposes into elemental magnesium (Mg) and oxygen gas (O\u2082).
This reaction typically requires electrolysis<\/strong> or a high temperature.<\/li>\n<\/ol>\n\n\n\n\n
\u2705 B. 2Mg + O\u2082<\/strong><\/h3>\n\n\n\n
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<\/figure>\n","protected":false},"excerpt":{"rendered":"