What planet have very little atmosphere

If a hydrogen atom is neutral, it must also have  one electron. an oxygen atom (o) has an atomic number of eight (8). this means a neutral oxygen atom has eight protons and eight electrons. the element actium (ac) has an atomic number of 89, so it has 89 protons and 89 electrons in a neutral atom

Sun is explosive itself spread 9 planets.earth is 3rd explosive in the solar system about 500 hundred million years ago . first earth became ice age and freezing climate.centre of earth magma. north zone is artic . south is anatric

Both models are effective because they show the valence electrons, and these valence electrons indicate the reactivity of an element.

It is a mixture. simply put, a compound must be pure, that is, of only one chemical structure and composition. a mixture is made of different chemical substances (i.e. elements, molecules, compounds) that are not chemically bonded to each other, but instead physically grouped together, as in the case of gasoline (a homogeneous solution).