{"id":223068,"date":"2025-06-01T08:05:37","date_gmt":"2025-06-01T08:05:37","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=223068"},"modified":"2025-06-01T08:05:39","modified_gmt":"2025-06-01T08:05:39","slug":"gockululian-mass-of-fluorescein-molar-mass-of-fluorescein-sodium-volume-9590-ethanol-concentration-methylene-black-solution-concentration-of-fluorescein-stock-solution-ppm-mol-l-preparation-of-standar","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/06\/01\/gockululian-mass-of-fluorescein-molar-mass-of-fluorescein-sodium-volume-9590-ethanol-concentration-methylene-black-solution-concentration-of-fluorescein-stock-solution-ppm-mol-l-preparation-of-standar\/","title":{"rendered":"Gockululian Mass of Fluorescein Molar mass of Fluorescein sodium Volume 9590 ethanol Concentration Methylene Black solution Concentration of fluorescein stock solution ppm mol\/L Preparation of standard solutions Fluorescein solution Fluorescein solution Fluorescein solution Fluorescein solution Fluorescein solution Fluorescein solution 150 06 ppmL ppI pu ppm ppm ppm The absorption and emission spectra of fluorescein."},"content":{"rendered":"\n<p>Gockululian Mass of Fluorescein Molar mass of Fluorescein sodium Volume 9590 ethanol Concentration Methylene Black solution Concentration of fluorescein stock solution ppm mol\/L Preparation of standard solutions Fluorescein solution Fluorescein solution Fluorescein solution Fluorescein solution Fluorescein solution Fluorescein solution 150 06 ppmL ppI pu ppm ppm ppm The absorption and emission spectra of fluorescein. The calibration curve Fluorescence MX Solution concentration Fluorescence intensity Calculation of the ppm concentration for unknown mol<br>Gockululian Mass of Fluorescein Molar mass of Fluorescein sodium Volume 9590 ethanol Concentration Methylene Black solution Concentration of fluorescein stock solution ppm mol\/L Preparation of standard solutions Fluorescein solution Fluorescein solution Fluorescein solution Fluorescein solution Fluorescein solution Fluorescein solution 150 06 ppmL ppI pu ppm ppm ppm The absorption and emission spectra of fluorescein. The calibration curve Fluorescence MX Solution concentration Fluorescence intensity Calculation of the ppm concentration for unknown mol<\/p>\n\n\n\n<p><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-1-color\">The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n<p>To provide a meaningful answer and explanation to your query, I will assume you are conducting a <strong>fluorescence spectroscopy experiment<\/strong> involving <strong>fluorescein<\/strong> and possibly <strong>methylene blue<\/strong>, where you are:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>Preparing standard solutions of <strong>fluorescein<\/strong>,<\/li>\n\n\n\n<li>Measuring their <strong>fluorescence intensity<\/strong>,<\/li>\n\n\n\n<li>Constructing a <strong>calibration curve<\/strong>, and<\/li>\n\n\n\n<li>Using this to calculate the <strong>concentration of an unknown fluorescein solution<\/strong> in <strong>ppm and mol\/L<\/strong>.<\/li>\n<\/ol>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Correct Answer with Example Calculation<\/strong><\/h3>\n\n\n\n<h4 class=\"wp-block-heading\"><strong>Given\/Assumed Data:<\/strong><\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Mass of fluorescein sodium used<\/strong>: 150 mg = 0.150 g<\/li>\n\n\n\n<li><strong>Molar mass of fluorescein sodium<\/strong>: 376.27 g\/mol<\/li>\n\n\n\n<li><strong>Volume of ethanol used to dissolve fluorescein<\/strong>: 95.90 mL = 0.0959 L<\/li>\n\n\n\n<li><strong>Concentration of Methylene Blue solution<\/strong>: Not relevant unless used as a comparison or quencher<\/li>\n\n\n\n<li><strong>Goal<\/strong>: Calculate <strong>stock solution concentration<\/strong> in <strong>ppm<\/strong> and <strong>mol\/L<\/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\"><strong>1. Moles of Fluorescein Sodium:<\/strong><\/h3>\n\n\n\n<p>Moles=MassMolar&nbsp;Mass=0.150376.27=3.987\u00d710\u22124&nbsp;mol\\text{Moles} = \\frac{\\text{Mass}}{\\text{Molar Mass}} = \\frac{0.150}{376.27} = 3.987 \\times 10^{-4} \\text{ mol}<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>2. Concentration in mol\/L:<\/strong><\/h3>\n\n\n\n<p>Concentration&nbsp;(mol\/L)=3.987\u00d710\u221240.0959=4.16\u00d710\u22123&nbsp;mol\/L\\text{Concentration (mol\/L)} = \\frac{3.987 \\times 10^{-4}}{0.0959} = 4.16 \\times 10^{-3} \\text{ mol\/L}<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>3. Convert to ppm (mg\/L):<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Since <strong>1 mol of fluorescein sodium = 376.27 g = 376,270 mg<\/strong>:<\/li>\n<\/ul>\n\n\n\n<p>Concentration&nbsp;in&nbsp;ppm=4.16\u00d710\u22123&nbsp;mol\/L\u00d7376270&nbsp;mg\/mol=1565&nbsp;ppm\\text{Concentration in ppm} = 4.16 \\times 10^{-3} \\text{ mol\/L} \\times 376270 \\text{ mg\/mol} = 1565 \\text{ ppm}<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Explanation <\/strong><\/h3>\n\n\n\n<p>In fluorescence spectroscopy, accurate preparation and quantification of the fluorophore (here, fluorescein sodium) are essential for producing reliable results. Fluorescein is a widely used fluorescent dye due to its strong fluorescence emission under UV light, and it is often used in tracing, biomedical imaging, and analytical chemistry.<\/p>\n\n\n\n<p>To prepare a stock solution, a known mass of fluorescein sodium\u2014150 mg in this case\u2014is dissolved in a solvent (95.90 mL of ethanol). The molar mass of fluorescein sodium (376.27 g\/mol) allows us to convert this mass into moles, yielding 3.987 \u00d7 10\u207b\u2074 mol. Dividing this by the solution volume gives a molarity of 4.16 \u00d7 10\u207b\u00b3 mol\/L.<\/p>\n\n\n\n<p>For practical comparisons and calibration, we often express concentration in parts per million (ppm), especially when dealing with dilute solutions. Using the molarity and the molar mass, we calculate a concentration of approximately 1565 ppm. This solution can then be used to prepare a dilution series (e.g., 150, 60, 30, 15 ppm, etc.) to build a <strong>calibration curve<\/strong> by plotting fluorescence intensity versus known concentration.<\/p>\n\n\n\n<p>This curve is crucial: once the fluorescence intensity of an <strong>unknown sample<\/strong> is measured, its concentration can be determined using the linear relationship from the calibration plot.<\/p>\n\n\n\n<p>This approach ensures accurate quantification of fluorescein in unknown samples and highlights the utility of fluorescence as a sensitive and selective analytical technique.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/learnexams.com\/blog\/wp-content\/uploads\/2025\/06\/learnexams-banner4-30.jpeg\" alt=\"\" class=\"wp-image-223069\"\/><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>Gockululian Mass of Fluorescein Molar mass of Fluorescein sodium Volume 9590 ethanol Concentration Methylene Black solution Concentration of fluorescein stock solution ppm mol\/L Preparation of standard solutions Fluorescein solution Fluorescein solution Fluorescein solution Fluorescein solution Fluorescein solution Fluorescein solution 150 06 ppmL ppI pu ppm ppm ppm The absorption and emission spectra of fluorescein. The [&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-223068","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/223068","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=223068"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/223068\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=223068"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=223068"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=223068"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}