When 1 mole of N₂ (g) reacts with O₂ (g) to form NO₂ (g) according to the following equation, 66.4 kJ of energy are absorbed. N₂(g) +202(g) → 2NO2 (9) Is this reaction endothermic or exothermic? What is the value of q? kJ

Nitrogen oxide (NO) has been found to be a key component in many biological processes. It also can react with oxygen to give the brown gas NO2. When one mole of NO reacts with oxygen, 57.0 kJ of heat are evolved. How many grams of nitrogen oxide must react with an excess of oxygen to liberate 20 kJ of heat? NO(g) + ½O2(g) → NO2(g) ΔH = –57.0 kJ ___________ g

How much energy is required to decompose 1970 g of PCl3, according to the reaction below?    4 PCl3(g) → P4(s) + 6 Cl2(g)                                             ΔH°RXN = +1207 kJ

Charcoal is primarily carbon. What mass of CO2 is produced if you burn enough carbon (in the form of charcoal) to produce 4.80 x 10² kJ of heat? The balanced chemical equation is as follows: C(s) + O2 (g) → CO2 (g), Express the mass in grams to three significant figures. VE ΑΣΦ m = ? g AHxn=-393.5 kJ

In the following reaction, how much heat is generated when 3.21 moles of CH4 are burned? CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O(g) AH° = -802 kJ/mol

A chemist measures the energy change AH during the following reaction: 2 H₂O(l) → 2 H₂(g) + O₂(g) ΔΗ= 572. kJ Use the information to answer the following questions. This reaction is... Suppose 64.5 g of H₂O react. Will any heat be released or absorbed? If you said heat will be released or absorbed in the second part of this question, calculate how much heat will be released or absorbed. Round your answer to 3 significant digits. O endothermic. O exothermic. O Yes, absorbed. O Yes, released. O No. 0 kJ x10 Start over

Determine the amount of heat released when 180.00 g AsBr5(g) reacts according to the following equation: As4O10(g) + 6 AsBr5(g)  →  10 Br3AsO(g) Additional equations that may be useful: 1/4 As4(s) + 3/2 Br2(g)  →  AsBr3(g)  ΔH = -336.4 kJ/mol As4(s) + 5 O2(g)  →  As4O10(g) ΔH = -2967.3 kJ/mol AsBr3(g) + Br2(g)  →  AsBr5(g)  ΔH = -84.2 kJ/mol AsBr3(g) + 1/2 O2(g)  →  Br3AsO(g)  ΔH = -295.7 kJ/mol

Consider these reactions: Reaction 1: H2 (g) + Cl2 (g) → 2HC1(g) AH = -184.6 kJ Reaction 2: 20F2 (9) → 02 (9) + 2 F2 (9) AH= -49.4 kJ Reaction 3: N2 (g) + 202(g) → 2NO2(g) AH=+66.4 kJ Use Reaction 2. How much energy (in kJ) is released when 61.0 g of oxygen difluoride decomposes? Answer: - kJ (enter a positive value)

A 7.37 g sample of an unknown salt (MM = 116.82 g/mol) is dissolved in 150.00 g water in a coffee cup calorimeter. Before placing the sample in the water, the temperature of the salt and water is 23.72°C. After the salt has completely dissolved, the temperature of the solution is 28.54°C. What quantity in moles of the unknown salt were used in the reaction?