What is similar about all the valence electrons for all the elements un the p-block?

List four observations that indicate that a chemical reaction may be taking place

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

To find the enthalpy of a reaction in the lab, you measured the of the reactants and the change during the reaction.