# Question #35da6

Jun 25, 2015

#### Explanation:

A chemical formula will give you information about what type of atoms and in what proportion make up a certain compound.

Take, for example, water, ${H}_{\textcolor{red}{2}} O$.

The fact that you need $\textcolor{red}{2}$ atoms of hydrogen and 1 atom of oxygen to form 1 water molecule is expressed using subscripts.

With the exception of 1, which is not written explicitly, any interger that follows an atom as a subscript will tell you exactly how many atoms of a certain type are found in a molecule.

Take a look at the molecular formula of sulfuric cid, ${H}_{2} S {O}_{4}$.

The subscripts that follow each type of atom will tell you exactly how many hydrogen, sulfur, and oxygen atoms are needed to form *1 molecule( of sulfuric acid. In this case, you have

• 2 atoms of hydrogen;
• 1 atom of sulfur (remember that 1 is not written explicitly);
• 4 atoms of oxygen.

One more example. Glucose has the molecular formula ${C}_{6} {H}_{12} {O}_{6}$. If you look at the subscripts listed, you can tell that 1 molecule of sucrose contains

• 6 atoms of carbon;
• 12 atoms of hydrogen;
• 6 atoms of oxygen.