Question

fill in the systematic names of the following chemical compounds.
note: for compounds containing hydrogen, you may give the common name instead.
molecular formula name of compound
pcl₃
cl₂o₇
pcl₅
cl₂o₃
nh₃

Explanation:

For naming covalent compounds, we use prefixes to indicate the number of each type of atom. The prefixes are: mono - (1, but usually omitted for the first element), di - (2), tri - (3), tetra - (4), penta - (5), hexa - (6), hepta - (7), octa - (8), nona - (9), deca - (10). The second element in the name has the suffix - ide.

• For \(PCl_{3}\): There is 1 phosphorus (\(P\)) atom (prefix "tri" for 3 chlorine (\(Cl\)) atoms). So it is phosphorus trichloride.
• For \(Cl_{2}O_{7}\): There are 2 chlorine (\(Cl\)) atoms (prefix "di") and 7 oxygen (\(O\)) atoms (prefix "hepta"). So it is dichlorine heptoxide.
• For \(PCl_{5}\): There is 1 phosphorus (\(P\)) atom and 5 chlorine (\(Cl\)) atoms (prefix "penta"). So it is phosphorus pentachloride.
• For \(Cl_{2}O_{3}\): There are 2 chlorine (\(Cl\)) atoms (prefix "di") and 3 oxygen (\(O\)) atoms (prefix "tri"). So it is dichlorine trioxide.
• For \(NH_{3}\): The common name for \(NH_{3}\) is ammonia.

Answer:

• \(PCl_{3}\): phosphorus trichloride
• \(Cl_{2}O_{7}\): dichlorine heptoxide
• \(PCl_{5}\): phosphorus pentachloride
• \(Cl_{2}O_{3}\): dichlorine trioxide
• \(NH_{3}\): ammonia