Which substance is in excess when 6.00 moles of aluminum are reacted with 12.00 moles of oxygen in the following equation?
4Al + 30. --> 2Al2O

D. is the answer hope that you

Heat is involved in chemical change in two ways; chemical changes either result in heat being added to or removed from an object, and chemical changes require a certain amount of heat before they can take place.

Idon't mean to be a smart alec, length of atoms' bonds is the simplest way to define it.

Well you can immediately rule out a and d because if a metal were to lose or gain protons, then it would become a different element all together. the answer here is b because the positive symbol with a number refers to how many electrons the metal can give away to become stable.