{"id":203681,"date":"2025-03-20T12:33:53","date_gmt":"2025-03-20T12:33:53","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=203681"},"modified":"2025-03-20T12:33:54","modified_gmt":"2025-03-20T12:33:54","slug":"if-the-freezing-point-of-blood-is-0-52-c","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/03\/20\/if-the-freezing-point-of-blood-is-0-52-c\/","title":{"rendered":"If the freezing point of blood is -0.52 C"},"content":{"rendered":"\n

If the freezing point of blood is -0.52 C, what is its osmotic pressure at 25\u00b0C? What is the vapor pressure lowering of blood at this temperature?<\/p>\n\n\n\n

The correct answer and explanation is :<\/strong><\/mark><\/p>\n\n\n\n

To solve for both osmotic pressure<\/strong> and vapor pressure lowering<\/strong> of blood, we need to consider colligative properties.<\/p>\n\n\n\n

1. Osmotic Pressure Calculation<\/strong><\/h3>\n\n\n\n

Osmotic pressure ((\\Pi)) is given by:<\/p>\n\n\n\n

[
\\Pi = iMRT
]<\/p>\n\n\n\n

where:<\/p>\n\n\n\n

    \n
  • ( i ) = Van\u2019t Hoff factor (for blood plasma, we approximate it as 1.9<\/strong> since it contains a mix of ions and molecules),<\/li>\n\n\n\n
  • ( M ) = molarity of solutes,<\/li>\n\n\n\n
  • ( R ) = ideal gas constant = 0.0821 L\u00b7atm\/(mol\u00b7K)<\/strong>,<\/li>\n\n\n\n
  • ( T ) = temperature in Kelvin (25\u00b0C = 298 K<\/strong>).<\/li>\n<\/ul>\n\n\n\n

    The freezing point depression<\/strong> equation helps us find M<\/strong>:<\/p>\n\n\n\n

    [
    \\Delta T_f = i K_f M
    ]<\/p>\n\n\n\n

    where:<\/p>\n\n\n\n

      \n
    • ( \\Delta T_f = 0.52\u00b0C ),<\/li>\n\n\n\n
    • ( K_f ) for water = 1.86\u00b0C\u00b7kg\/mol<\/strong>.<\/li>\n<\/ul>\n\n\n\n

      Solving for M<\/strong>:<\/p>\n\n\n\n

      [
      M = \\frac{0.52}{(1.9 \\times 1.86)} = 0.148 \\text{ mol\/kg}
      ]<\/p>\n\n\n\n

      Approximating molarity \u2248 molality<\/strong> for dilute solutions:<\/p>\n\n\n\n

      [
      \\Pi = (1.9)(0.148)(0.0821)(298)
      ]<\/p>\n\n\n\n

      [
      \\Pi \\approx 7.3 \\text{ atm}
      ]<\/p>\n\n\n\n

      2. Vapor Pressure Lowering<\/strong><\/h3>\n\n\n\n

      Vapor pressure lowering is given by Raoult\u2019s Law<\/strong>:<\/p>\n\n\n\n

      [
      \\Delta P = X_{\\text{solute}} P_{\\text{solvent}}
      ]<\/p>\n\n\n\n

      where:<\/p>\n\n\n\n

        \n
      • ( X_{\\text{solute}} \\approx \\frac{0.148}{55.5} = 0.00267 ),<\/li>\n\n\n\n
      • ( P_{\\text{solvent}} ) (vapor pressure of pure water at 25\u00b0C) = 23.8 mmHg<\/strong>.<\/li>\n<\/ul>\n\n\n\n

        [
        \\Delta P = (0.00267)(23.8) \\approx 0.064 \\text{ mmHg}
        ]<\/p>\n\n\n\n

        Final Answer:<\/strong><\/h3>\n\n\n\n
          \n
        • Osmotic Pressure<\/strong> \u2248 7.3 atm<\/strong>.<\/li>\n\n\n\n
        • Vapor Pressure Lowering<\/strong> \u2248 0.064 mmHg<\/strong>.<\/li>\n<\/ul>\n\n\n\n

          These values explain how blood maintains osmotic balance and minimizes water loss via evaporation.<\/p>\n","protected":false},"excerpt":{"rendered":"

          If the freezing point of blood is -0.52 C, what is its osmotic pressure at 25\u00b0C? What is the vapor pressure lowering of blood at this temperature? The correct answer and explanation is : To solve for both osmotic pressure and vapor pressure lowering of blood, we need to consider colligative properties. 1. Osmotic Pressure […]<\/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-203681","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/203681","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=203681"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/203681\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=203681"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=203681"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=203681"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}