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754db7c7-5916-47d0-8177-cf2c1d8dde3d Recognize different formats of expressing heat of reaction Summary The heat of reaction (∆H) represents the amount of heat energy gained or lost during a chemical reaction. It can be expressed in different formats depending on the specific information provided. Let's analyze each option and identify the equivalent equations for the given reaction: a) N2(g) + 2O2(g) → 2NO2(g) ΔH = +68 kJ: This equation is an equivalent representation of the given reaction. It explicitly states that the heat of reaction (∆H) is +68 kJ, indicating that the reaction releases 68 kJ of heat energy. c) 1⁄2N2(g) + O2(g) → NO2(g) ΔH = + 34 kJ: This equation is also an equivalent representation of the given reaction. It differs from the original equation by using the stoichiometric coefficients to balance the reaction. It shows that the heat of reaction (∆H) is +34 kJ, indicating the release of 34 kJ of heat energy. d) N2(g) + 2O2(g) → 2NO2(g) ΔH = +68 kJ/mol N2: This equation is another valid representation of the given reaction. It includes the molar quantity of nitrogen gas (N2) and specifies the heat of reaction (∆H) per mole of nitrogen gas. It indicates that for each mole of N2, the heat of reaction is +68 kJ. f) N2(g) + 2O2(g) → 2NO2(g) ΔH = +34 kJ/mol NO2: This equation is also an equivalent representation of the given reaction. It includes the molar quantity of nitrogen dioxide (NO2) and specifies the heat of reaction (∆H) per mole of nitrogen dioxide. It indicates that for each mole of NO2, the heat of reaction is +34 kJ. The remaining options (b) and (e) are not equivalent to the given reaction: b) N2(g) + 2O2(g) → 2NO2(g) ΔH = -68 kJ: This equation incorrectly states that the heat of reaction (∆H) is -68 kJ, suggesting that the reaction absorbs 68 kJ of heat energy. This contradicts the given information of the reaction releasing heat energy. e) 1⁄2N2(g) + O2(g) → NO2(g) ΔH = −34 kJ: This equation incorrectly states that the heat of reaction (∆H) is -34 kJ, indicating that the reaction absorbs 34 kJ of heat energy. Again, this contradicts the given information of the reaction releasing heat energy. In summary, the equivalent equations to the given reaction N2(g) + 2O2(g) + 68 kJ → 2NO2(g) are options a), c), d), and f). These equations accurately represent the given reaction and provide information about the heat of reaction (∆H) in various formats, including the heat change per mole of N2 or NO2.

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96efce51-ac42-4f1e-ac1d-4e33adbf23a4 2 construct and interpret a reaction pathway diagram, in terms of the enthalpy change of the reaction and of the activation energy Summary Constructing and interpreting a reaction pathway diagram allows us to visualize the energy changes that occur during a chemical reaction. This diagram, also known as an energy profile or reaction energy diagram, illustrates the progression of a reaction from reactants to products along the reaction pathway. The vertical axis of the reaction pathway diagram represents the energy content of the system, typically measured in terms of enthalpy (H). The horizontal axis represents the progress of the reaction from left to right, going from the reactants to the products. The diagram includes three key components: the reactants, the products, and the energy changes that occur during the reaction. The enthalpy change (∆H) of the reaction is represented by the difference in energy between the reactants and the products. If the reactants have a higher enthalpy than the products, the ∆H value is negative, indicating an exothermic reaction. Conversely, if the products have a higher enthalpy than the reactants, the ∆H value is positive, indicating an endothermic reaction. On the reaction pathway diagram, the enthalpy change (∆H) is shown as the vertical distance between the energy levels of the reactants and products. For an exothermic reaction, the products' energy level is lower than that of the reactants, resulting in a negative ∆H. In contrast, for an endothermic reaction, the products' energy level is higher, leading to a positive ∆H. Additionally, the reaction pathway diagram illustrates the activation energy (Ea) of the reaction. The activation energy represents the energy barrier that must be overcome for the reaction to proceed. It is the minimum energy required for the reactant molecules to reach the transition state and form the products. On the reaction pathway diagram, the activation energy is shown as the energy difference between the reactants and the highest energy point on the reaction pathway, known as the transition state or the activated complex. The activation energy determines the reaction rate and influences the speed at which the reaction occurs. By examining the reaction pathway diagram, we can interpret various aspects of the reaction. The height of the energy barrier (activation energy) indicates the difficulty of the reaction. A higher activation energy implies a slower reaction rate, while a lower activation energy suggests a faster reaction. The overall enthalpy change (∆H) can be calculated by comparing the energy levels of the reactants and products. It represents the difference in energy content between the initial and final states of the system. The enthalpy change, along with the activation energy, provides valuable insights into the energy profile and kinetics of the reaction. Understanding and interpreting a reaction pathway diagram allows chemists to analyze the energy changes involved in a reaction. It helps predict the feasibility, rate, and overall energy requirements of the reaction. By examining the enthalpy change and activation energy, we can gain a deeper understanding of the reaction's thermodynamics and kinetics. In summary, constructing and interpreting a reaction pathway diagram enables us to visualize and analyze the energy changes and activation energy of a chemical reaction. The diagram provides insights into the enthalpy change (∆H) between reactants and products, as well as the energy barrier required for the reaction to occur. By examining these components, we can assess the reaction's energy profile, feasibility, and rate, enhancing our understanding of chemical kinetics and thermodynamics.

SABIS Grade 10 T1 W2

4d273e93-9c73-4a5f-a142-6b5097399467 Boyle's Law Summary The principle that states the volume of a given amount of gas is inversely proportional to its pressure at a constant temperature.

321f9bcf-34b5-4b82-803f-7215e00967a2 Halogens: F2 (Z = 9), Cl2 (Z = 17), Br2 (Z = 35) and I2 (Z = 53). Summary

2b1008c9-a189-4e20-b7ee-37766cc77bb0 At STP there are 10 gaseous elements. 5 monoatomic: helium(He), neon(Ne), argon(Ar), krypton(Kr), and xenon(Xe); 5 daitomic: fluorine(F2), chlorine(Cl2), oxygen(O2), hydrogen(H2) and nitrogen(N2) Summary

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684fb4ba-d7b8-4380-962d-b63edd43ceb5 Cooking a steak until it is well done Summary Chemical

Revision AMS and Periodic Term 2 Week 5 Week 16 January 2025 SABIS Grade 9 Revision AMS and Periodic Term 2 Week 5 Written By Mr. Hisham Mahmoud. Last Revision 17.1.2025 Do not forget the fractionating column with glass beads to delay the second gas and slows it to help fractional distillation of liquids with similar or close boiling points Written By Mr. Hisham Mahmoud. Last Revision 17.1.2025