Use standard enthalpies of formation to calculate ΔH∘rxn for the following reaction: 2H2S(g)+3O2(g)→2H2O(l)+2SO2(g)

How many moles of al3+ ions are in 1.25 moles of al2o3

Earth's axis of rotation is tilted at an angle of 23.5 degrees. what is one change you would see on earth if its axis was not tilted?

How many protons, electrons, and neutrons are in each of the following isotopes? a. zirconium-90 b. palladium-108 c. bromine-81 d. antimony-123