Question

1. by now you should be able to answer the following questions. if not, do another collection and pay attention to the following.

a) what does the big 2 in ( 2\text{co}_2 ) mean?
b) what does the little 2 in ( 2\text{co}_2 ) mean?
challenge

1. use the atoms available to try and build a larger molecule!

a) name of molecule:
chemical formula:

of total elements:

of total atoms:

sketch: box for sketch

Explanation:

Part 6a

In a chemical formula, a coefficient (the big number) in front of a compound formula indicates the number of molecules of that compound. For \(2\text{CO}_2\), the big 2 is a coefficient.

In a chemical formula, a subscript (the little number) after an element symbol indicates the number of atoms of that element in one molecule of the compound. For \(2\text{CO}_2\), the little 2 is a subscript after O.

• Name of Molecule: Water is a common molecule. Its chemical formula is \( \text{H}_2\text{O} \).
• Chemical Formula: \( \text{H}_2\text{O} \) has 2 elements (hydrogen and oxygen) and a total of \(2 + 1=3\) atoms.
• Sketch: Represent oxygen (e.g., a larger circle) in the center with two hydrogen atoms (smaller circles) bonded to it (lines or pairs of dots for covalent bonds).

Answer:

The big 2 in \(2\text{CO}_2\) means there are 2 molecules of carbon dioxide.

Part 6b