The symbol for magnesium is Mg, and sulfuric acid is a compound containing sulfur, oxygen, and hydrogen. Its formula is written: H2SO4. So we write Mg plus H2SO4. An arrow shows the direction of ...

For example, sodium chloride has the same number of sodium ions and chloride ions, so its formula is NaCl, whereas water is always made from twice the number of hydrogen atoms as oxygen atoms ...

Not only do people need oxygen to breathe, which Mars’ atmosphere sorely lacks ... greatly accelerating the generation of a reliable model and finding of an optimal formula," the study's authors write ...