Question

why? when you began chemistry class this year, you probably already knew that the chemical formula for carbon dioxide was co₂. today you will find out why co is named that way. naming chemical compounds correctly is of paramount importance. the slight difference between the names carbon monoxide (co, a poisonous, deadly gas) and carbon dioxide (co₂, a greenhouse gas that we exhale when we breathe out) can be the difference between life and death! in this activity you will learn the naming system for molecular compounds. model 1 - molecular compounds molecular formula number of atoms of first element number of atoms of second element name of compound clf 1 1 chlorine monofluoride clf₅ 1 5 chlorine pentafluoride co 1 1 carbon monoxide co₂ 1 2 carbon dioxide cl₂o 2 1 dichlorine monoxide n₂o₅ 2 5 dinitrogen pentoxide 1) fill in the table to indicate the number of atoms of each type in the molecular formula. 2) ionic compounds have a metal and a nonmetal in them. molecules like those in model 1 are called molecular compounds. do the molecules in model 1 have a metal and nonmetal or 2 nonmetals? are the compounds in model 1 ionic or molecular? the molecules in model 1 have 2 non - metals 3) what is different about the names in model 1 than the name of ionic compounds we named last week? number of atoms 4) clf and clf₅ both have chlorine and fluorine in them. why is the name “chlorine fluoride” not sufficient to identify these compounds? have different ratios 5) the name of the compound gives a clue to its molecular formula. how many fluoride atoms are there in carbon monofluoride? using the trends in model 1, predict how many atoms each of these prefixes indicates. di - penta -

Explanation:

Step1: Analyze molecular formulas for atoms

For $ClF$, there is 1 chlorine (Cl) and 1 fluorine (F) atom. For $ClF_5$, 1 Cl and 5 F atoms. For $CO$, 1 carbon (C) and 1 oxygen (O) atom. For $CO_2$, 1 C and 2 O atoms. For $Cl_2O$, 2 Cl and 1 O atoms. For $PCl_5$, 1 phosphorus (P) and 5 Cl atoms. For $N_2O_5$, 2 nitrogen (N) and 5 O atoms.

Step2: Determine compound type

The compounds in Model 1 (e.g., $ClF$, $CO$) consist of non - metals only. So they are molecular compounds. Ionic compounds have a metal and a non - metal, which is not the case here.

Step3: Compare naming

Names of molecular compounds in Model 1 use prefixes (mono -, di -, penta - etc.) to indicate the number of atoms of each element. Ionic compound names do not use such prefixes in the same way; they follow different naming rules based on charges.

Step4: Explain naming insufficiency

$ClF$ and $ClF_5$ have different ratios of chlorine to fluorine. Just "chlorine fluoride" does not specify the ratio, so it is not sufficient to identify the compounds.

Step5: Predict atom numbers from prefixes

In carbon monofluoride, "mono -" indicates 1. The prefix "di -" indicates 2 atoms and "penta -" indicates 5 atoms.

Answer:

1.

Molecular Formula	Number of Atoms of First Element	Number of Atoms of Second Element
$ClF_5$	1	5
$CO$	1	1
$CO_2$	1	2
$Cl_2O$	2	1
$PCl_5$	1	5
$N_2O_5$	2	5

1. The compounds in Model 1 are molecular. They consist of non - metals only.
2. Molecular compound names use prefixes to indicate atom numbers, while ionic compound names follow different rules not based on such prefixes for atom - number indication.
3. Because $ClF$ and $ClF_5$ have different ratios of chlorine to fluorine, and "chlorine fluoride" does not specify the ratio.
4. In carbon monofluoride, there is 1 fluoride atom. "di -" indicates 2 atoms and "penta -" indicates 5 atoms.