How many protons, neutrons, and electrons are in potassium, nitrogen, and oxygen?

The amount of protons is equal to the number of electrons of a chemical element. The atomic number of an element also determines the number of the protons it contains. The number of protons is also the same number of electrons. Protons are positively charged, electrons are negatively charged. To get the number of neutrons, all you need is to deduct the number of  the atomic mass or mass number from the atomic number. Potassium has 19 protons, therefore has 19 electrons as well. The atomic mass of Potassium is 39. So, the number of neutrons Potassium has is 20. Potassium Atomic number: 19 Protons: 19 Electrons: 19 Atomic Mass: 39 Neutron: 20 Nitrogen Atomic number: 7 Protons: 7 Electrons: 7 Atomic Mass: 14.007 Neutrons: 7 Oxygen Atomic Number: 8 Protons: 8 Electrons: 8 Atomic Mass: 15.99 Neutrons: 8

They can measure  the amount of energy gained or lost

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.