* All separate questions that I needs answers to* Thank you
What element has 12 electrons when the atom is electrically neutral?
What element is in the alkaline-earth metals group and has 20 protons?
This element has 7 electrons when the atom is electrically neutral?

Coal i believe hope this

Idon't see the pic?

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).