The two ways to measure the sand in a sand castle are by counting the number of pails of sand used to build the castle and by determining the mass of the sand used in building the castle. The first method makes use of the volume of the pail to determine the amount of sand while the second method is a more quantitative way.<span />
Answer:
stars
earth isn't made of gas. (and you can always see it)
moon us not gas, or give off heat
sun is only visible during the day
Answer:
Ionic compounds
Explanation:
Molecular formula consists of chemical symbols for constituent elements followed by the numeric subscripts describing number of the atoms of each element present in one molecule of the compound.
On the other hand, ionic compounds do not exist in the form of molecules. They are in the form of crystal lattice in the solid state which contains many ions each of cation and anion.
<u>Thus, a ionic compounds are unable to write a molecular formula. Empirical formulas to used to represent them.</u>