the sum of the masses of individual nuclear particles is less than their masses when combined?

Question

true or false

Answer 1

True. The difference is the binding energy, which is released when the nucleons are combined, as when hydrogen is combined to make helium in the sun.

Answer 2

If you go along the periodic table from hydrogen to the heavy transuranic elements, helium is more stable than hydrogen. When two hydrogens fuse to make helium, a lot of energy is released and the helium nucleus weighs less than the two hydrogens. Then as you continue to heavier elements, they become less stable until you get to element 42; technetium. You have to put energy into lighter elements to fuse them into heavier ones, so two heliums weigh less than the beryllium nucleus they make. From technetium to iron, element 56, the nuclei get progressively more stable. Iron is the most stable of any nucleus. From iron onwards, nuclei get progressively less stable, so a uranium nucleus weighs more than the fragments you get when you split it. The rule is, if you get energy released when you split a nucleus, then the whole weighs more than its parts.

Answer 3

Generally true. It's called 'fusion' and it's what generates all the energy in a fusion bomb (or 'H' bomb)

HTH ☺

Doug