Ions form the number of an atom is changed? Question options:

proton

neutron

atomic number

electron

(It was not Atomic number)

Electron

Explanation:

"standard molar enthalpy:

h2o ( liquid water ) : - 285.8 kj/mole

h2o ( water vapor ) : - 241.8 kj / mole.

δhrxn = - 241. 8 - ( - 285.8 )= -241.8 + 285.8 = 44.0

answer: 44.0 kj"

it's c. elements are placed in rows based on how may valencies electrons have.