The nucleus has almost the mass of the atom. It is made up of protons (+) and neutrons (0)

1/100,000

Explanation:

its radius is only about 1/100,000 of the total radius of the atom. if an atom were the size of a football stadium, the nucleus would be about the size of a pea! Electrons have virtually no mass, but protons and neutrons have a lot of mass for their size. As a result, the nucleus has virtually all the mass of an atom.

with this one i know the answer in craters one reason i looked it up and i learned about it there is my evidence

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.