What is the change in enthalpy when 0.350 moles of B₂H6 react with excess O₂ according to the following blanced chemical reacton: B₂H6(g) + 3 O₂(g) → B₂O3(s) + 3 H₂O(g) ΔΗ = -2035 | J

Consider the hypothetical thermochemical equation 3 A + B → 2 C for which AH = 63.1 kJ/mol. Which one of the following reactions would have an enthalpy change of -2×AH? Here, AH refers to the enthalpy change of the original reaction. А) С — 3/2 А + 1/2 В B) 6 A + 2 B –→ 4 C С) 3/2 А + 1/2 В — С D) 4 C → 6 A + 2 B

A chemist carefully measures the amount of heat needed to raise the temperature of a 0.81kg sample of C4H6O2 from 31.4c to 49.6c. The experiment shows that 2.48*10^4 J of heat are needed. what can the chemist report for the molar heat capacity of C4H6O2 ? Round your answer to 2 sig figs.

Consider the following reaction. CH3OH(g)  CO(g) + 2 H2(g)    H = +90.7 kJ ((b) Calculate the amount of heat transferred when 40.0 g of CH3OH(g) are decomposed by this reaction at constant pressure.H =  kJ(c) If the enthalpy change is 20.0 kJ, how many grams of hydrogen gas are produced? g(d) How many kilojoules of heat are released when 12.5 g of CO(g) reacts completely with H2(g) to form CH3OH(g) at constant pressure?H =   kJ(e) Calculate E when 880.0 g of CH3OH(g) completely reacts at a constant temperature of 300 K and constant pressure of 0.95 atm. R = 8.314 J/mol*K and R = 0.08206 atm*L/mol*K   kJ HopHelpCh5N1

From the following data, C (graphite) + O₂(g) → CO₂(g) H₂(g) + —⁄- 02₂(g) → H₂O (1) CH₂(g) + 20₂(g) → CO₂(g) + 2H₂O (1) kJ ×10 Calculate the enthalpy change for the reaction below: C(graphite) + 2H₂(g) CH4 (g) Be sure your answer has the correct number of significant digits. X → ΔΗ° S rxn ΔΗ° = -285.8 rxn = -393.5 ΔΗ° = -890.4 rxn kJ mol kJ mol kJ mol

You mix 125 mL of 0.250 M CSOH with 50.0 mL of 0.625 M HF in a coffee-cup calorimeter, and the temperature of both solutions rises from 21.70 °C before mixing to 24.59 °C after the reaction. CsOH(aq) + HF (aq) → CsF(aq) + H₂O(l) What is the enthalpy of reaction per mole of CSOH? Assume the densities of the solutions are all 1.00 g/mL, and the specific heat capacities of the solutions are 4.2 J/g. K. Enthalpy of reaction = kJ/mol

Sulfur dioxide, SO2(g), can react with oxygen to produce sulfur trioxide, SO3(g), by the reaction 2 SO2(g) + O2(g) → 2 SO3(g) The standard enthalpies of formation for SO2(g) and SO3(g) are AH; [SO2(g)] = -296.8 kJ/mol AH; [SO3(g)] = -395.7 kJ/mol Calculate the amount of energy in the form of heat that is produced when a volume of 2.25 L of SO2(g) is converted to 2.25 L gas behavior. of SO3(g) according to this process at a constant pressure and temperature of 1.00 bar and 25.0 °C. Assume ideal AH= kJ

Draw an enthalpy diagram to represent the following equation:  Pb(s) + PbO2(s) + 2H2SO4(aq) → 2PbSO4(s) + 2H2O(l) ∆H = –509 kJ

When methanol, CH3OH,CH3OH, is burned in the presence of oxygen gas, O2,O2, a large amount of heat energy is released. For this reason, it is often used as a fuel in high performance racing cars. The combustion of methanol has the balanced, thermochemical equation CH3OH(g)+32O2(g)⟶CO2(g)+2H2O(l)ΔH=−764 kJCH3OH(g)+32O2(g)⟶CO2(g)+2H2O(l)ΔH=−764 kJ How much methanol, in grams, must be burned to produce 639 kJ639 kJ of heat?

What is the mas of natural gas (CH4) must you burn to emit 276 kJ of heat?