Reason : Enthalpy of formation of most stable allotrope is taken as zero. The formation of diamond from graphite is simply a phase transformation given by . Solution: 1) Multiply chemical equation (2) by 2: 2SO 3 + 2H 2 O ---> 2H 2 SO 4 ΔH = −226 kJ. If both A and R are true,but R is not the true explanation of A. Información sobre tu dispositivo y conexión a Internet, incluida tu dirección IP, Actividad de navegación y búsqueda al utilizar sitios web y aplicaciones de Verizon Media. At 300 K, the enthalpy difference between diamond and graphite is Ahd-g = 1900 J/mole, with diamond less stable than graphite in this regard. CBSE board exam 2021 preparation tips to ace the exam. Yahoo forma parte de Verizon Media. That is, graphite is the stable phase at all temperatures at atmospheric pressure. At 1 atm and 25°C, diamond changes to graphite so slowly that the enthalpy change of the process must be obtained indirectly. MP board exam 2021 class 10 & 12 syllabus reduced by 30%. Correct option (b) Both A and R are true but R is not correct explanation of A. NEET 2020 Admissions - MBBS seats reserved for child of COVID-19 warriors who lost their lives due to COVID-19 or died accidentally during COVID-19 duty. CBSE 2021 exam tips will definitely help you to score the highest marks in the board exam. Expressions and Identities, Direct The change in enthalpy gotten from adding up the individual steps that lead to an overall reaction has to be the same as the change in enthalpy of the overall reaction. of Derivatives, Application Assertion (A) : Graphite is chemically more reactive than diamond . Thermodynamically graphite is more stable than diamond but diamond does not transform into graphite on its own. 1:31 11.2k LIKES schools to start the course on responsible use of social media. 2) Switch the reactants and products in chemical reaction (2).
(ii) Graphite has higher electrical conductivity than diamond. Given that the enthalpies of combustion of graphite and diamond are 393.5 and 395.4 kJ mol –1 respectively. Explanation: Greater entropy of graphite is related to its structure as graphite is less compact and rigid than diamond. of Integrals, Continuity Answer and Explanation: C(diamond) C(graphite) 1) C(diamond) + O2(g) CO2(g) ΔH = -395.4 kJ. The enthalpies of combustion of diamond and graphite are - 395.4 kJ and - 393.5 kJ respectively calculate the enthalpy of transformation from diamond to graphite. Algebraic Informations sur votre appareil et sur votre connexion Internet, y compris votre adresse IP, Navigation et recherche lors de l’utilisation des sites Web et applications Verizon Media. If we add reactions, how do we manipulate the enthalpy changes? At 25 C, the enthalpy of the graphite to diamond phase transition is 1.8961 kJ/mol, and the entropy change is -3.2552 J/Kmol. Determine the enthalpy of reaction for the discharge reaction above. Diamond-Graphite Equilibria. Conversely IT IS POSSIBLE for you to turn graphite into diamonds under extreme heat and pressure. Apne doubts clear karein ab Whatsapp (8 400 400 400) par of Parallelograms and Triangles, Introduction Some Amazon rainforest regions more resistant to climate change than previously thought. Hess's Law describes the relationship between the enthalpy values when reactions are added. Being a highly ordered structure, diamond has a molar entropy lower than that of graphite, and Asd-g = -3.3 J/mole-K (see Fig. On the basis of enthalpy of formation, graphite is more stable than diamond, yet diamond does not change into graphite for years. Because of that, the sign of the change in enthalpy becomes positive. At 1 atm and 25°C, diamond changes to graphite so slowly that the enthalpy change of the process must be obtained indirectly.
Reason. Yahoo fait partie de Verizon Media. Découvrez comment nous utilisons vos informations dans notre Politique relative à la vie privée et notre Politique relative aux cookies. CBSE Class 12 Exam 2021 - Exam Pattern and New Marking Scheme. Being a highly ordered structure, diamond has a molar entropy lower than that of graphite, and Asd-g = -3.3 J/mole-K (see Fig. CBSE Board Exam 2021 Preparation Tips to Ace the Exam. (1) Cgraphite =Cdiamond. Nosotros y nuestros socios almacenaremos y/o accederemos a la información de tu dispositivo mediante el uso de cookies y tecnologías similares, a fin de mostrar anuncios y contenido personalizados, evaluar anuncios y contenido, obtener datos sobre la audiencia y desarrollar el producto. Pour autoriser Verizon Media et nos partenaires à traiter vos données personnelles, sélectionnez 'J'accepte' ou 'Gérer les paramètres' pour obtenir plus d’informations et pour gérer vos choix. Assertion (A) : Diamond is a good conductor of electricity
Reason (R) : Diamond and graphite are two allotrope carbon and graphite is a good conductor of electricity. This difference also favors the stability of graphite. 3.6). Diamonds can’t and won’t turn into graphite, atleast practically.
Reason (R) : Diamond is very hard but fraphite si soof .
Graphite has higher, Assertion Diamond and graphite do not have same crystal structure. and Differentiability. bhi. CBSE has reduced the syllabus for class 10 & 12 exam 2021, date sheet can release soon. Assertion (A): Enthalpy of graphite is lower than that of diamond. At 300 K, the enthalpy difference between diamond and graphite is Ahd-g = 1900 J/mole, with diamond less stable than graphite in this regard. Determine ΔHrxn for the following with equations from the list below.
(iii) Graphite has higher thermal conductivity than diamond. Draw an energy diagram for the reaction C graphite C diamond making sure to show whether the reaction is endothermic or exothermic. With respect to graphite and diamond, which of the statements given below are correct? Calculate the enthalpy change accompanying the transformation of C (graphite) to C(diamond). Know NCERT guidelines to safe & ethical use of online platforms by the students. Nov 20, 2020. Check complete JEE Main 2021 exam update and other important details related to exams! to Trigonometry, Complex to Three Dimensional Geometry, Application Question From class 11 Chapter THERMODYNAMICS. What is the spontaneous direction for the reaction at 25 C? Graphite and diamond are two forms of the same chemical element, carbon.
Reason (R) : Graphite has a hree -dimensional structure while diamond has planer struture . Explanation: Greater entropy of graphite is related to its structure as graphite is less compact and rigid than diamond. Delhi Govt. Diamond and graphite are two crystalline forms of carbon. Try it now. From the entropy and enthalpy changes you found above, calculate the Gibbs free energy change … What will be the enthalpy change of conversion of graphite into diamond? Numbers and Quadratic Equations, Introduction JEE Main 2021 January session likely to be postponed to February. 2) 2 CO2(g) 2 CO(g) + O2(g) ΔH = 566.0 kJ That is because graphite is the standard state of carbon, not diamond. The enthalpies of combustion of diamond and graphite are - 395.4 kJ and - 393.5 kJ respectively calculate the enthalpy of transformation from diamond to graphite. Graphite is a much better conductor of heat and electricity than diamond. Why ? JEE Main 2021: January Session likely to be postponed to February. Delhi Govt. Know steps to download MPBSE syllabus & complete details related to the MP board exam 2021! Para obtener más información sobre cómo utilizamos tu información, consulta nuestra Política de privacidad y la Política de cookies. Notice that if we reverse the second reaction and then add the first reaction, the net reaction is the conversion of graphite to diamond! Correct option (b) Both A and R are true but R is not correct explanation of A. NEET 2020 - 5 MBBS Seats Reserved for Wards of COVID-19 Warriors.
Reason (R ) : Entropy of graphite is lower than that of diamond. Vous pouvez modifier vos choix à tout moment dans vos paramètres de vie privée. Type your answer here: Graphite ---> Diamond is an exothermic process 5. Although graphite is thermodynamically most stable allotrope of Carbon but it has more entropy than diamond Because: Assertion : Enthalpy of formation of graphite is zero but fo diamond is not zero. Para permitir a Verizon Media y a nuestros socios procesar tus datos personales, selecciona 'Acepto' o selecciona 'Gestionar ajustes' para obtener más información y para gestionar tus opciones, entre ellas, oponerte a que los socios procesen tus datos personales para sus propios intereses legítimos. That is because graphite is the standard state of carbon, not diamond.
(i) Graphite is harder than diamond. Related to Circles, Introduction At atmospheric pressures the Gibb's energy change for the reaction is greater than zero at all temperatures.