{"id":199049,"date":"2025-03-10T17:15:20","date_gmt":"2025-03-10T17:15:20","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=199049"},"modified":"2025-03-10T17:15:23","modified_gmt":"2025-03-10T17:15:23","slug":"how-many-milligrams-mg-would-you-use-to-make-15-ml-of-a-250-millimolar-mm-kcl-solution","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/03\/10\/how-many-milligrams-mg-would-you-use-to-make-15-ml-of-a-250-millimolar-mm-kcl-solution\/","title":{"rendered":"How many milligrams (mg) would you use to make 15 ml of a 250 millimolar (MM) KCl solution"},"content":{"rendered":"\n<p>How many milligrams (mg) would you use to make 15 ml of a 250 millimolar (MM) KCl solution? Answer mg 6. How many milligrams (mg) would you use to make 75 ml of a 800 micromolar (UM) KCl solution? Answer mg<br><\/p>\n\n\n\n<p><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-6-color\">The correct answer and explanation is:<\/mark><\/strong><\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Answers:<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>For 15 ml of a 250 mM KCl solution:<\/strong><br><strong>279.56 mg<\/strong><\/li>\n\n\n\n<li><strong>For 75 ml of an 800 \u00b5M KCl solution:<\/strong><br><strong>4.47 mg<\/strong><\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Explanation<\/h3>\n\n\n\n<p>To prepare chemical solutions accurately, understanding molar concentration calculations is essential. The two given problems demonstrate converting molar concentrations into mass measurements required for making laboratory solutions.<\/p>\n\n\n\n<p><strong>1. Preparing 15 ml of a 250 mM KCl solution:<\/strong><\/p>\n\n\n\n<p>First, convert volume to liters: 15\u2009ml=151000=0.015\u2009L15\\,ml = \\frac{15}{1000} = 0.015\\,L<\/p>\n\n\n\n<p>Next, convert concentration from millimolar (mM) to molar (M): 250\u2009mM=2501000=0.25\u2009mol\/L250\\,mM = \\frac{250}{1000} = 0.25\\,mol\/L<\/p>\n\n\n\n<p>To find the mass needed, use the formula: Mass&nbsp;(g)=Concentration&nbsp;(mol\/L)\u00d7Volume&nbsp;(L)\u00d7Molecular&nbsp;Weight&nbsp;(g\/mol)\\text{Mass (g)} = \\text{Concentration (mol\/L)} \\times \\text{Volume (L)} \\times \\text{Molecular Weight (g\/mol)}<\/p>\n\n\n\n<p>The molecular weight of potassium chloride (KCl) is 74.55 g\/mol. Thus, the calculation is: 0.25\u2009mol\/L\u00d70.015\u2009L\u00d774.55\u2009g\/mol=0.27956\u2009g0.25\\,mol\/L \\times 0.015\\,L \\times 74.55\\,g\/mol = 0.27956\\,g<\/p>\n\n\n\n<p>Convert this to milligrams: 0.27956\u2009g\u00d71000=279.56\u2009mg0.27956\\,g \\times 1000 = 279.56\\,mg<\/p>\n\n\n\n<p>Hence, 279.56 mg of KCl is required.<\/p>\n\n\n\n<p><strong>2. Preparing 75 ml of an 800 \u00b5M KCl solution:<\/strong><\/p>\n\n\n\n<p>Similarly, first convert volume to liters: 75\u2009ml=751000=0.075\u2009L75\\,ml = \\frac{75}{1000} = 0.075\\,L<\/p>\n\n\n\n<p>Convert micromolar (\u00b5M) to molar (M): 800\u2009\u00b5M=8001,000,000=0.0008\u2009mol\/L800\\,\u00b5M = \\frac{800}{1,000,000} = 0.0008\\,mol\/L<\/p>\n\n\n\n<p>Using the same formula: 0.0008\u2009mol\/L\u00d70.075\u2009L\u00d774.55\u2009g\/mol=0.004473\u2009g0.0008\\,mol\/L \\times 0.075\\,L \\times 74.55\\,g\/mol = 0.004473\\,g<\/p>\n\n\n\n<p>Convert this to milligrams: 0.004473\u2009g\u00d71000=4.47\u2009mg0.004473\\,g \\times 1000 = 4.47\\,mg<\/p>\n\n\n\n<p>Thus, only 4.47 mg of KCl is required for the second solution.<\/p>\n\n\n\n<p>The difference in mass required between these two solutions highlights the importance of precise calculations for accurate concentrations in laboratory settings.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>How many milligrams (mg) would you use to make 15 ml of a 250 millimolar (MM) KCl solution? Answer mg 6. How many milligrams (mg) would you use to make 75 ml of a 800 micromolar (UM) KCl solution? Answer mg The correct answer and explanation is: Answers: Explanation To prepare chemical solutions accurately, understanding [&hellip;]<\/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-199049","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/199049","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=199049"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/199049\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=199049"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=199049"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=199049"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}