The empirical formula is the simplest formula of a compound. It depicts the ratio of atoms of each element in the compound. It can be obtained by dividing the percentage by mass of each element by its relative atomic mass. The lowest ratio obtained is now used to divide all the previously obtained ratios and whole number values are recorded. This shows the ratio of atoms of each element present, hence the empirical formula.
They are called the terrestrial planets and are smaller than the others. They are he hottest planets and closest to the sun and take less time to rotate the sun.