Chemistry: Covalent Compounds

The name for P2O5 is diphosphorus pentoxide. There is more than one of each element in the compound so prefixes must be used for both elements, which eliminates phosphorus pentoxide and phosphorus oxide as possible names. Diphosphorus pentaoxygen has the correct prefixes, but since there are two vowels in a row, the a should be dropped from penta. Additionally, the suffix of oxygen should be changed to -ide. Prefix Meaning Prefix Meaning mono 1 hexa 6 di 2 hepta 7 tri 3 octa 8 tetra 4 nona 9 penta 5 deca 10

The name for NCl3 is nitrogen trichloride. No prefix is needed for nitrogen because there is only one nitrogen atom. The prefix tri- is used for chlorine to indicate that there are three chlorine atoms in the formula.

The name for CBr4 is carbon tetrabromide. The prefix for carbon is omitted because there is only one atom of carbon. The prefix tetra- represents four bromine atoms in the molecule.

The name for As2O5 is diarsenic pentoxide. The chemical symbol for arsenic is "As" and since there are two arsenic atoms, the di- prefix must be used. The five oxygens in the formula are indicated by the penta- prefix. However, the a is dropped from the prefix to eliminate a double vowel in the name. The symbol for argon is "Ar", and as a noble gas, it does not form covalent compounds.

The name for N2O is dinitrogen monoxide. Nitrogen oxide is incorrect because nitrogen needs a prefix to indicate two atoms and oxygen needs a prefix because it is the second element.

The name for N2O3 is dinitrogen trioxide. The prefix di- indicates that there are two nitrogen atoms, and trioxide indicates that there are three oxygen atoms in the formula.

The name for SbBr3 is antimony tribromide. No prefix is needed for the antimony because there is only one atom and it is the first element in the compound. Tribromide indicates that there are three atoms of bromine in the compound.

The balanced reaction for the decomposition of NO2 is 2NO2 → N2 + 2O2. The formula for nitrogen dioxide is NO2 and both nitrogen and oxygen exist as diatomic elements.

The name monocarbon monooxide is incorrect for CO because a prefix should not be used for carbon and the letter o should be dropped from prefix for oxygen. If there is only one of the first element, the prefix can be dropped. This does not apply to the second element. If a prefix ends in o or a and the element starts with a vowel, the o or a is dropped. The elements are named in the same order that they are given in the formula.

The formula for phosphorus trihydride is PH3. The name for P3H is triphosphorus monohydride, and the name for P2H3 is diphosphorus trihydride.

The IUPAC name for NH3 is nitrogen trihydride. A prefix is not needed for the nitrogen since there is only one atom of the nitrogen in the compound and it is the first element. Trihydride represents the three hydrogen atoms in the formula.

The formula for nitrogen monoxide is NO. There is only one atom of nitrogen in the compound so nitrogen does not need a prefix. The prefix mono- is used for oxygen to indicate that there is one atom of oxygen.

The name for CO2 is carbon dioxide. Since there is only one atom of the first element, as in CO2, the prefix for the first element is dropped. The prefix for oxygen is di- to represent the two oxygen atoms.

The name for P4S3 is tetraphosphorus trisulfide. Tetraphosphorus indicates that there are four atoms of phosphorus and trisulfide represents the three atoms of sulfur. The formula for triphosphorus tetrasulfide is P3S4 and PS3 is the formula phosphorus trisulfide. Tetraphosphide trisulfide uses the correct prefixes but the suffix of the first element in the name should remain unchanged.

The name for B2Cl4 is diboron tetrachloride. Boron tetrachloride is incorrect because there is more than one atom of boron, so it must have a prefix included in its name.

The name for ICl3 is iodine trichloride. Iodine does not have a prefix because it is the first element and there is only one atom of iodine. The prefix tri- indicates three for the number of atoms of chlorine. The correct names and formulas for the other compounds are shown in the table. ClF3 chlorine trifluoride XeO6 xenon hexoxide KrF4 krypton tetrafluoride KrF7 krypton heptafluoride

The formula for silicon dioxide is SiO2. The lack of a prefix before silicon indicates that there is only one atom of silicon in the compound. The prefix di- indicates that there are two oxygen atoms in the formula.

The formula for tetraboron decahydride is B4H10. The prefix tetra- indicates four atoms of boron and deca- before hydride means there are ten atoms of hydrogen.

The name for hydrazine, N2H4, is dinitrogen tetrahydride.

The formula for dihydrogen monoxide is H2O, commonly known as "water". Dihydrogen indicates that there are two hydrogen atoms and monoxide indicates that there is one oxygen atom. While the statements in this story are true, the message is very misleading.

The name for SO3 is sulfur trioxide. Sulfur does not need a prefix because it is the first element and there is only one atom. The prefix tri- indicates that there are three oxygen atoms in the formula.

The name for B2H6 is diboron hexahydride. The prefix di- is used to indicate the two atoms of boron and hexa- indicates the six atoms of hydrogen. The formula for diboron heptahydride is B2H7. The prefix tri-, used in triboron hexhydride (B3H6) and triboron heptahydride (B3H7) indicates three atoms of boron which does not match the given formula.

The name for N2O5 is dinitrogen pentoxide. The two atoms of nitrogen require the prefix di- to be used and the five oxygen atoms in the formula are represented by pentoxide.

The name for SF6 is sulfur hexafluoride. The lack of a prefix for sulfur indicates that there is one atom of sulfur in the formula. Hexafluoride is used to represent the six fluorine atoms in the formula.

The formula for dihydrogen monosulfide is H2S because dihydrogen indicates that there are two hydrogen atoms along with the one sulfur atom indicated by monosulfide.

The formula for phosphorus pentabromide is PBr5. Phosphorus is the first element and does not have a prefix, which indicates that there is only one phosphorus atom in the formula. Pentabromide indicates that there are five bromine atoms in the formula.

he correct name for ClO2 is chlorine dioxide. With the name dioxide monochlorine, the elements are given in the wrong order and the prefix mono- should be omitted from the chlorine. In naming covalent compounds, the names for the element are given in the same order as shown in the formula, the suffix of the second element is changed to -ide, and prefixes are used to indicate the number of atoms of each element. The prefix for the first element is omitted if there is only one atom of that element.

The formula for xenon trioxide is XeO3. The lack of a prefix for xenon indicates that there is one atom of xenon in the formula and trioxide represents the three oxygen atoms. Note that i is not dropped from the prefix name even though it creates a double vowel in the name. The vowel is only dropped from the prefix when it ends in an o or a.

The formula for tetraphosphorus nonasulfide is P4S9. Tetraphosphorus indicates that there are four atoms of phosphorus and nonasulfide represents the nine atoms of sulfur.

The name for IF7 is iodine heptafluoride. A prefix is not needed for the iodine, as there is only one atom of the element and it is the first element in the compound. The prefix hepta- indicate that there are seven atoms of fluorine in this compound.