Based on the enthalpy changes given for the reactions, which reactions are endothermic? 2H2O → 2H2 + O2, ΔH = 484 kJ C + O2 → CO2, ΔH = -394 kJ H2 + Br2 → 2HBr, ΔH = -73 kJ 2NH3 → N2 + 3H2, ΔH = 92 kJ

How have the greenhouse gasses increased from the year 2000 to 2018

Ican determine the molar mass of an element by looking on the under the atomic mass for the element. for example the molar mass of phosphorus is 30.974 grams/mole. avogadro’s number tells me the amount of representative particles in 1 mole of any substance. this means 12.011 gram sample of carbon and a 32.0 gram sample of sulfur have the same number of atoms.

Which of the following is the correct definition of chemical energy? a. energy an object has because of its motion or position b. energy resulting from the flow of charged particles, such as electrons or ions c. energy produced from the splitting of atoms d. energy stored in chemical bonds of molecules