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For the reaction C+ ( C (s) + 02 (9) ----CO2 (9) delta H = - 393.5 kJ Calculate the heat evolved when 18 g of C (s) react, is the reaction endothermic or exothermic? 01.-590.3 k); exothermic 2.+ 1180.5 kJ exothermic 03.+590 3 kJ endothermic 04.-1180.5 kJ, endothermic A Moving to another question will save this response.

User Piotr Kula
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Final answer:

In the given exothermic reaction, when 18g of Carbon (C) reacts, about 590.3 kJ of heat is evolved.

Step-by-step explanation:

In this question, we're asked to calculate how much heat is evolved when 18 g of Carbon (C) reacts in an exothermic reaction. The given reaction, C(s) + O2(g) ---> CO2(g) ΔH = -393.5 kJ, is exothermic, meaning it releases heat. ΔH is negative, confirming this. We can use this to calculate the heat evolved for 18g of C. One mole of C (12g) releases 393.5 kJ of heat, so 18g of C would release more.

To solve, we set up a proportionality: 12g of C is to 393.5 kJ as 18g of C is to X kJ. Solving for X gives us X = (18g * 393.5 kJ) / 12g, which equals roughly 590.3 kJ. Therefore, when 18g of Carbon reacts, about 590.3 kJ of heat is evolved, and this reaction is exothermic.

Learn more about Exothermic Reactions

User Andri Kurnia
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