{"id":204706,"date":"2025-03-22T13:24:01","date_gmt":"2025-03-22T13:24:01","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=204706"},"modified":"2025-03-22T13:24:03","modified_gmt":"2025-03-22T13:24:03","slug":"determine-the-ph-of-0-265-m-hclo-solution","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/03\/22\/determine-the-ph-of-0-265-m-hclo-solution\/","title":{"rendered":"Determine the pH of 0.265 M HClO solution"},"content":{"rendered":"\n

Determine the pH of 0.265 M HClO solution. The Ka of HClO is 2.9 x 10^-8<\/p>\n\n\n\n

answers could be\u2026<\/p>\n\n\n\n

a) 0.576<\/p>\n\n\n\n

b) 8.11<\/p>\n\n\n\n

c) 5.89<\/p>\n\n\n\n

d) 4.06<\/p>\n\n\n\n

c)3.31<\/p>\n\n\n\n

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

To determine the pH of a 0.265 M HClO (hypochlorous acid) solution, we need to account for the dissociation of HClO in water. HClO is a weak acid, meaning it does not completely dissociate in water. Instead, it establishes an equilibrium between its undissociated form (HClO) and its dissociated ions (H+ and ClO\u2212).<\/p>\n\n\n\n

The dissociation reaction of HClO is:<\/p>\n\n\n\n

[
\\text{HClO} \\rightleftharpoons \\text{H}^+ + \\text{ClO}^-
]<\/p>\n\n\n\n

The equilibrium constant, Ka, is given as:<\/p>\n\n\n\n

[
\\text{Ka} = 2.9 \\times 10^{-8}
]<\/p>\n\n\n\n

Step 1: Set up the ICE table (Initial, Change, Equilibrium)<\/h3>\n\n\n\n

We will use an ICE (Initial, Change, Equilibrium) table to track the concentrations of the species involved in the dissociation.<\/p>\n\n\n\n

Species<\/th>Initial (M)<\/th>Change (M)<\/th>Equilibrium (M)<\/th><\/tr><\/thead>
HClO<\/td>0.265<\/td>-x<\/td>0.265 – x<\/td><\/tr>
H+<\/td>0<\/td>+x<\/td>x<\/td><\/tr>
ClO\u2212<\/td>0<\/td>+x<\/td>x<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

Step 2: Write the expression for Ka<\/h3>\n\n\n\n

The equilibrium constant expression for this dissociation is:<\/p>\n\n\n\n

[
\\text{Ka} = \\frac{[H^+][ClO^-]}{[HClO]} = \\frac{x \\cdot x}{0.265 – x}
]<\/p>\n\n\n\n

This simplifies to:<\/p>\n\n\n\n

[
2.9 \\times 10^{-8} = \\frac{x^2}{0.265 – x}
]<\/p>\n\n\n\n

Step 3: Make an approximation<\/h3>\n\n\n\n

Since Ka is very small, we can assume that the amount of dissociation (x) will be small compared to the initial concentration of HClO (0.265 M). Thus, ( 0.265 – x \\approx 0.265 ). Substituting this into the equation:<\/p>\n\n\n\n

[
2.9 \\times 10^{-8} = \\frac{x^2}{0.265}
]<\/p>\n\n\n\n

Step 4: Solve for x<\/h3>\n\n\n\n

Now, solve for ( x ):<\/p>\n\n\n\n

[
x^2 = (2.9 \\times 10^{-8}) \\times 0.265
]<\/p>\n\n\n\n

[
x^2 = 7.685 \\times 10^{-8}
]<\/p>\n\n\n\n

[
x = \\sqrt{7.685 \\times 10^{-8}} = 8.77 \\times 10^{-4} \\text{ M}
]<\/p>\n\n\n\n

Step 5: Calculate pH<\/h3>\n\n\n\n

The concentration of H+ is equal to ( x ), so:<\/p>\n\n\n\n

[
[H^+] = 8.77 \\times 10^{-4} \\, \\text{M}
]<\/p>\n\n\n\n

The pH is given by:<\/p>\n\n\n\n

[
\\text{pH} = -\\log[H^+] = -\\log(8.77 \\times 10^{-4}) = 3.06
]<\/p>\n\n\n\n

Conclusion<\/h3>\n\n\n\n

The correct pH value is closest to 3.31<\/strong>. So, the correct answer is:<\/p>\n\n\n\n

c) 3.31<\/strong><\/p>\n","protected":false},"excerpt":{"rendered":"

Determine the pH of 0.265 M HClO solution. The Ka of HClO is 2.9 x 10^-8 answers could be\u2026 a) 0.576 b) 8.11 c) 5.89 d) 4.06 c)3.31 The correct answer and explanation is : To determine the pH of a 0.265 M HClO (hypochlorous acid) solution, we need to account for the dissociation of […]<\/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-204706","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/204706","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=204706"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/204706\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=204706"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=204706"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=204706"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}