Anions and cations attract one another by means of

Select all of the statements which are true. electrons are located in shells or orbits around the atom. electrons orbit slowly around the atom. electrons travel in one flat path around the nucleus of an atom. the valence of an atom is determined by the number of electrons in the atom's outermost shell.

Match the formula for the following compound:   magnesium sulfate heptahydratemgs·7h2omg2so4·7h2omg(so4)2·7h2omgso4·7h2o

Ok, so i have 2 questions. try to answer them both: (the topic is fire) 1) how can you represent the chemical reaction of fire? 2) what kind of bond is formed in this chemical reaction