Using the following reaction:4 Mg (s) + 2 O2 (g) → 4 MgO (s) H = -2408 kJ Calculate the amount of heat transferred when 4.2 g of Mg (s) reacts at constant pressure. a) -1204 kJ b) - 416 kJ c) - 208 kJ d) - 69 kJ e) - 104 kJ

Consider the reaction 2 H, + 0, — 2H,О AHrxn -484 kJ Which answer best describes the transfer of heat that occurs when 1.50 mol H, reacts? 363 kJ released 363 kJ absorbed 484 kJ released 726 kJ absorbed 726 kJ released 484 kJ absorbed

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

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A 5.43 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. If -3.13 x 10 J of heat was lost during the dissolution reaction of 0.0465 moles of the unknown salt, what is the enthalpy change (in kJ/mol of salt) for the dissolution reaction? Type here to search

Consider the following equation for the combustion of H₂: 1 H₂(g) + H₂(g) + O₂(g) → O₂(g) → H H₂O(g) + 243 kJ In order to produce 972 kJ of heat, what mass of H₂ must burn?

The answer is 44.8 kJ/mol. Show the solution how to get 44.8 kJ/mol.

Consider the reaction   2H2+O2⟶2H2OΔ?rxn=−484 kJ Which answer best describes the transfer of heat that occurs when 1.40 mol H2 reacts?   678 kJ absorbed 484 kJ released 339 kJ released 678 kJ released 484 kJ absorbed 339 kJ absorbed

When 25.0 g hydrogen gas react according to the following reaction, how many kJ of heat are released or consumed? CO (g)    +   3 H2 (g)   -->   CH4 (g)   +   H2O (g)      Delta Hrxn =  – 206 kJ a. – 1.28 x 103 J b. – 25.5 J c. – 639 J d. – 2.55 x 103 J e. – 1.29 x 103 J f. none of these

Consider these reactions: Reaction 1: H₂(g) + Cl₂ (g) Reaction 2: 20F2 (g) O2(g) +2 F2 (g) AH Reaction 3: N₂(g) + 2O2(g) → 2NO₂(g) AH = +66.4 kJ Use Reaction 1. — → 2HCl(g) AH = -184.6 kJ g = -49.4 kJ Determine the mass, in grams, of chlorine gas consumed (with excess H₂) when 1,959.0 kJ of energy is released from the system. Round to the nearest whole number. Answer: