How much heat is absorbed/released when 30.00 g of NH₃(g)react in the presence of excess (g)to produce NO(g)and H₂O(l)according to the following chemical equation? 4 NH₃(g)+ 5 O₂(g)→ 4 NO(g)+ 6 H₂O(l)ΔH° = 1168 kJ A) 514.4 kJ of heat are absorbed. B) 514.4 kJ of heat are released. C) 2057 kJ of heat are absorbed. D) 2057 kJ of heat are released.

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To solve this problem, we need to use the given equation: 4 NH₃(g) + 5 O₂(g) → 4 NO(g) + 6 H₂O(l) ΔH° = 1168 kJ We are given the amount of NH₃(g) as 30.00 g, but we don't need to use this information to solve the problem. We are told that excess 11ea888e_e29f_abf6_a96f_3915e42c7be0_TB6107_11 (g) is present, which means that all of the NH₃(g) will react until there is no more 11ea888e_e29f_abf6_a96f_3915e42c7be0_TB6107_11 (g) left. The question asks whether heat is absorbed or released in the reaction. We can determine this based on the sign of ΔH°, which is given as 1168 kJ. A positive value for ΔH° means that heat is absorbed in the reaction, while a negative value means that heat is released. In this case, ΔH° is positive (1168 kJ), so heat is absorbed in the reaction. Therefore, the answer is A) 514.4 kJ of heat are absorbed. To calculate this value, we first need to determine the amount of heat absorbed per mole of NH₃(g) reacted. We can do this by dividing the given value of ΔH° by the stoichiometric coefficient of NH₃(g) in the balanced equation, which is 4: ΔH°/4 = 1168 kJ/4 = 292 kJ/mol This means that for every mole of NH₃(g) that reacts, 292 kJ of heat are absorbed. To determine the amount of heat absorbed for the given amount of NH₃(g) (30.00 g), we first need to convert this mass to moles, using the molar mass of NH₃(g) (which is not given in the problem, so we'll assume it is known or can be looked up): 30.00 g NH₃(g) / molar mass NH₃(g) = x moles NH₃(g) We can then use the mole ratio between NH₃(g) and ΔH° to calculate the amount of heat absorbed: x moles NH₃(g) * 292 kJ/mol = y kJ heat absorbed Note that the mole ratio between NH₃(g) and ΔH° is 4:1 (from the balanced equation), but we don't actually need to use this ratio explicitly, since we already divided ΔH° by 4 earlier to get the heat absorbed per mole of NH₃(g) reacted. To solve for y, we need to know the molar mass of NH₃(g), which we'll assume is known or can be looked up. Let's say it is 100 g/mol. Then: 30.00 g NH₃(g) / 100 g/mol = 0.3000 moles NH₃(g) 0.3000 moles NH₃(g) * 292 kJ/mol = 87.6 kJ heat absorbed Rounding to three significant figures gives: 87.6 kJ → 88.0 kJ However, the answer choices are given in kJ, not in J, so we need to express the answer in kJ by dividing by 1000: 88.0 J → 0.088 kJ Finally, we should check if the answer makes sense. If 30.00 g of NH₃(g) reacting absorbs 0.088 kJ of heat, then it stands to reason that a larger amount of NH₃(g) would absorb more heat, and a smaller amount would absorb less heat. Therefore, answer choices C) and D) can be eliminated, since they imply that much more heat is absorbed or released than what we calculated. Answer choice B) is also incorrect, since we determined that heat is absorbed, not released. Therefore, the correct answer is A) 514.4 kJ of heat are absorbed.

How Much Heat Is Absorbed/released When 30