Question

montgomery county public schools draft 2018
hs ngss chemistry
naming binary molecular/covalent compounds
part i
nonmetal & nonmetal
there are three main rules one needs to follow in order to name binary molecular compounds. one pertains to the use of numerical prefixes, one to the use of -ide, and one to the use of mono. evaluate the three sets of molecular compounds and generate a rule for each set. utilize your rules to write the name of the molecular compound. remember that molecular/covalent compounds are formed from nonmetals.
rule 1: use of prefixes
diphosphorus pentoxide
dinitrogen tetroxide
tetraphosphorus hexoxide
rule 1:
prefix is the subscript
rule 2: use of -ide
diphosphorus pentoxide
carbon dioxide
sulfur dibromide
oxygen difluoride
rule 2:
rule 3: use of mono
carbon monoxide
dinitrogen monoxide
phosphorus trichloride
chlorine dioxide
rule 3:
part ii
write the chemical name for the following compounds using the rules generated in part i.

	formula	name
1.	n₂o₃	dinitrogen trioxide
2.	scl₂
3.	if₅	iodine pentafluoride
4.	sicl₄
5.	bcl₃
6.	ccl₄
7.	so₂
8.	co
9.	cl₂o₇
10.	co₂

Explanation:

Step1: Apply prefix & -ide rule

For $\text{SCl}_2$: S (sulfur, no mono), 2 Cl = di + chloride.

Step2: Apply prefix & -ide rule

For $\text{SiCl}_4$: Si (silicon, no mono), 4 Cl = tetra + chloride.

Step3: Apply prefix & -ide rule

For $\text{BCl}_3$: B (boron, no mono), 3 Cl = tri + chloride.

Step4: Apply prefix & -ide rule

For $\text{CCl}_4$: C (carbon, no mono), 4 Cl = tetra + chloride.

Step5: Apply prefix & -ide rule

For $\text{SO}_2$: S (sulfur, no mono), 2 O = di + oxide.

Step6: Apply mono & -ide rule

For $\text{CO}$: C (carbon, no mono), 1 O = mono + oxide.

Step7: Apply prefix & -ide rule

For $\text{Cl}_2\text{O}_7$: 2 Cl = di + chlorine, 7 O = hepta + oxide.

Step8: Apply prefix & -ide rule

For $\text{CO}_2$: C (carbon, no mono), 2 O = di + oxide.

Answer:

1. $\text{N}_2\text{O}_3$: dinitrogen trioxide
2. $\text{SCl}_2$: sulfur dichloride
3. $\text{IF}_5$: iodine pentafluoride
4. $\text{SiCl}_4$: silicon tetrachloride
5. $\text{BCl}_3$: boron trichloride
6. $\text{CCl}_4$: carbon tetrachloride
7. $\text{SO}_2$: sulfur dioxide
8. $\text{CO}$: carbon monoxide
9. $\text{Cl}_2\text{O}_7$: dichlorine heptoxide
10. $\text{CO}_2$: carbon dioxide