2. Write the formula or name for the following

compounds:

a. P205

b. CCl2

c. boron trichloride

d. dinitrogen tetrahydride

Diphosphorus pentoxide

Carbon dichloride

BCl3

N2H4

Explanation:

These are all covalent compounds. To name covalent compounds, you add prefixes to the beginning of their names depending on what the subscript is of each element. The prefixes are:

1: Mono

2: Di

3: Tri

4: Tetra

5: Penta

6: Hexa

7: Hepta

8: Octa

9: Nona

10: Deca

For example, since the first one is Phopsphorus with a 2 next to it, you add the prefix Di to it.

If the first element in the compound only has one, meaning no number next to it, you do not say mono. This is why we just say "Carbon" for the second one instead of "Monocarbon."

Finally, you always have to end the second element in the compound with "ide." So, "chlorine" becomes "chloride," "oxygen" becomes "oxide," and so on.