Isotopes of an element have the same number of protons but different numbers of what? I have no idea what subject to put this under qwq

Isotopes is a phenomenon whereby atoms of the same element exhibit different mass numbers but have the same atomic number.I hope this helps... Thank you for the question

i believe it is-

d.) gravity pulled particles of dust and gas together to form planets.

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.