The combustion of propane is represented by the following chemical equation. C3H8(g)+5O2(g)⟶3CO2(g)+4H2O(l) The standard enthalpies of formation ( ΔH∘f ) for C3H8(g), CO2(g), and H2O(l) are −103.8 kJ/mol, −393.5 kJ/mol, and −285.8 kJ/mol respectively. What is the enthalpy of combustion for propane at 25 °C and 1 atm?

Which of the following has wavelength longer than the wavelength of viable light? a) x rays b) gamma rays c) radios waves d) ultraviolet waves

What was bohr’s contribution to the planetary model

Two metal blocks that have slightly different temperatures are placed next to one another. after five minutes, they both have lower but equal temperatures. according to the law of conservation of energy, what  most likelyhappened? energy was created inside the blocks.energy was destroyed inside the blocks.energy was absorbed into the blocks from outside the system.energy was transferred from the warmer block to the cooler block.