{"id":42470,"date":"2025-06-29T04:38:51","date_gmt":"2025-06-29T04:38:51","guid":{"rendered":"https:\/\/gaviki.com\/blog\/?p=42470"},"modified":"2025-06-29T04:38:52","modified_gmt":"2025-06-29T04:38:52","slug":"for-the-process-chcl2s-a%e2%80%a0-chcl3l-ih-9-17-kj-mol-and-is-43-9-j-molk","status":"publish","type":"post","link":"https:\/\/gaviki.com\/blog\/for-the-process-chcl2s-a%e2%80%a0-chcl3l-ih-9-17-kj-mol-and-is-43-9-j-molk\/","title":{"rendered":"For the process CHCl2(s) \u00e2\u2020\u2019 CHCl3(l), \u00ce\u201dH = 9.17 kJ\/mol and \u00ce\u201dS = 43.9 J\/molK."},"content":{"rendered":"\n

For the process CHCl2(s) \u00e2\u2020\u2019 CHCl3(l), \u00ce\u201dH = 9.17 kJ\/mol and \u00ce\u201dS = 43.9 J\/molK. What is the melting point of chloroform? 64 \u00c2\u00b0C (62209 %\u00e2\u201a\u00ac 1.17 K; Joule: Ag A4 T4$ 130 % 9.17 \u00c3\u2014 10^3 (43.9 \u00c3\u2014 64) % -130 % K+2s: 9.17 \u00c3\u2014 10^3 T( = 3.08 \u00c3\u2014 10^-3 43.9 s\/mole<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n

Correct Answer:<\/strong> a. -64 \u00b0C<\/p>\n\n\n\n

Explanation:<\/strong><\/p>\n\n\n\n

To find the melting point of chloroform, we need to determine the temperature at which the solid and liquid phases are in equilibrium. The provided chemical equation, CHCl\u2083(s) \u2192 CHCl\u2083(l), describes this melting process. According to the principles of thermodynamics, a system at equilibrium, such as a substance at its melting or boiling point, has a Gibbs free energy change (\u0394G) equal to zero.<\/p>\n\n\n\n

The Gibbs free energy equation relates enthalpy (\u0394H), entropy (\u0394S), and temperature (T):
\u0394G = \u0394H – T\u0394S<\/p>\n\n\n\n

For a phase change at equilibrium, we can set \u0394G to 0.
0 = \u0394H – T\u0394S<\/p>\n\n\n\n

This equation can be rearranged to solve for the temperature (T), which in this case represents the melting point.
T\u0394S = \u0394H
T = \u0394H \/ \u0394S<\/p>\n\n\n\n

Before calculating, it is crucial to ensure that the units are consistent. The problem provides \u0394H\u00b0 in kilojoules (kJ\/mol) and \u0394S\u00b0 in joules per mole Kelvin (J\/mol\u00b7K). We must convert one of the units to match the other. Let’s convert \u0394H\u00b0 from kilojoules to joules.
\u0394H\u00b0 = 9.17 kJ\/mol \u00d7 (1000 J \/ 1 kJ) = 9170 J\/mol<\/p>\n\n\n\n

Now, we can substitute the values for \u0394H\u00b0 and \u0394S\u00b0 into the formula to find the temperature in Kelvin (K).
T = (9170 J\/mol) \/ (43.9 J\/mol\u00b7K)
T \u2248 208.9 K<\/p>\n\n\n\n

The multiple choice options are in degrees Celsius (\u00b0C), so a final conversion from Kelvin to Celsius is necessary.
T(\u00b0C) = T(K) – 273.15
T(\u00b0C) = 208.9 K – 273.15
T(\u00b0C) \u2248 -64.25 \u00b0C<\/p>\n\n\n\n

The calculated melting point is approximately -64.25 \u00b0C. This value is closest to option (a), making -64 \u00b0C the correct answer.<\/p>\n\n\n\n

\"\"<\/figure>\n","protected":false},"excerpt":{"rendered":"

For the process CHCl2(s) \u00e2\u2020\u2019 CHCl3(l), \u00ce\u201dH = 9.17 kJ\/mol and \u00ce\u201dS = 43.9 J\/molK. What is the melting point of chloroform? 64 \u00c2\u00b0C (62209 %\u00e2\u201a\u00ac 1.17 K; Joule: Ag A4 T4$ 130 % 9.17 \u00c3\u2014 10^3 (43.9 \u00c3\u2014 64) % -130 % K+2s: 9.17 \u00c3\u2014 10^3 T( = 3.08 \u00c3\u2014 10^-3 43.9 s\/mole The […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-42470","post","type-post","status-publish","format-standard","hentry","category-quiz-questions"],"_links":{"self":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/42470","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/comments?post=42470"}],"version-history":[{"count":1,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/42470\/revisions"}],"predecessor-version":[{"id":42473,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/posts\/42470\/revisions\/42473"}],"wp:attachment":[{"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/media?parent=42470"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/categories?post=42470"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/gaviki.com\/blog\/wp-json\/wp\/v2\/tags?post=42470"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}