What is the atomic number of an atom that has 6 protons

Its atomic mass is 14 ( = 6 protons + 8 neutrons). In chemistry, the number of protons in an atom is more important than the number of neutrons. Scientists call the number of protons the "atomic number"

Explanation:

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.