Question

What is the systematic name of \(\mathrm{Ta}_{2} \mathrm{O}_{5}\) ? If the charge on the metal remained constant and then sulfur was substituted for oxygen, how would the formula change? What is the difference in the total number of protons between \(\mathrm{Ta}_{2} \mathrm{O}_{5}\) and its sulfur analog?

Short answer

The systematic name for \(\mathrm{Ta}_{2} \mathrm{O}_{5}\) is Tantalum(V) oxide. When sulfur is substituted for oxygen, the formula changes to \(\mathrm{Ta}_{2} \mathrm{S}_{5}\). The difference in the total number of protons between \(\mathrm{Ta}_{2} \mathrm{O}_{5}\) and its sulfur analog is 40 protons.

Step-by-step solution

Systematic name of \(\mathrm{Ta}_{2} \mathrm{O}_{5}\)

The compound is \(\mathrm{Tantalum}\) and \(\mathrm{Oxygen}\). As there are 2 Tantalum (Ta) and 5 Oxygen (O) atoms, the systematic (IUPAC) name will be Tantalum(V) oxide, using Roman numerals to denote the charge of the metal.

Determine the charge on the metal

As there are 5 Oxygen atoms with a charge of 2- (total: 10-), and the charge on the Tantalum must balance that, we can infer that each Tantalum has a charge of 5+ (according to the name, Tantalum(V) oxide).

Substitute sulfur for oxygen

To maintain the same charge on the Tantalum(V) ions, we need to balance the overall charges. The charge on a sulfur ion is also 2-. To balance the overall charges, we will have 2 Tantalum(V) ions with 5+ charge each, which equals 10+ in total. To balance the charges, we need 5 sulfur ions with a charge of 2- (total: 10-). Therefore, the formula for the sulfur analog is Ta_2S_5.

Determine the difference in the total number of protons

The atomic number of Tantalum (Ta) is 73, and the atomic number of Oxygen (O) is 8, while the atomic number of Sulfur (S) is 16. For \(\mathrm{Ta}_{2} \mathrm{O}_{5}\): Total number of protons = 2(Tantalum protons) + 5(Oxygen protons) = 2(73) + 5(8) = 146 + 40 = 186 For \(\mathrm{Ta}_{2} \mathrm{S}_{5}\): Total number of protons = 2(Tantalum protons) + 5(Sulfur protons) = 2(73) + 5(16) = 146 + 80 = 226

Find the difference in the total number of protons

Now, we find the difference in the total number of protons between \(\mathrm{Ta}_{2} \mathrm{O}_{5}\) and the sulfur analog: Difference = 226 - 186 = 40 protons So, the difference in the total number of protons between \(\mathrm{Ta}_{2} \mathrm{O}_{5}\) and its sulfur analog is 40 protons.

Key concepts

Chemical Nomenclature

Understanding the systematic naming of chemical compounds, known as chemical nomenclature, is crucial in chemistry to clearly and efficiently communicate about various substances. The International Union of Pure and Applied Chemistry (IUPAC) has guidelines to standardize these names.

Naming a compound typically involves identifying the elements present and the proportion in which they occur. For instance, in the compound \(\mathrm{Ta}_2 \mathrm{O}_5\), tantalum (Ta) and oxygen (O) are the constituents. This compound is named Tantalum(V) oxide, where 'oxide' indicates the presence of oxygen, and the Roman numeral V signifies the oxidation state of tantalum, which is +5. The oxidation state is essential because tantalum can form compounds in several oxidation states; thus, specifying it ensures there is no ambiguity.

The systematic naming system aids in predicting the properties of a compound, its structure, and its reactivity. For example, if you were to substitute sulfur (S) for oxygen, respecting the original oxidation states, you'd create Tantalum(V) sulfide, \(\mathrm{Ta}_2 \mathrm{S}_5\), by ensuring that the overall charge remains balanced.

Oxidation States

An oxidation state, also known as oxidation number, is a figure that represents the degree of oxidation of an atom in a chemical compound. It is a conceptual charge that an atom would have if all bonds to atoms of different elements were 100% ionic. This concept allows chemists to keep track of electron transfer in oxidation-reduction reactions.

In the compound \(\mathrm{Ta}_2 \mathrm{O}_5\), oxygen has a typical oxidation state of -2, and since there are five oxygen atoms, the total negative charge is 10-. To balance this, each tantalum atom must have an oxidation state of +5, hence two tantalum atoms give a total positive charge of 10+, balancing the negative charge from oxygen.

The ability to identify and balance oxidation states is important when predicting the outcome of chemical reactions. It provides an insight into the transfer of electrons, which is key to understanding how elements react to form compounds as well as the chemical behavior of the molecules.

Atomic Number

The atomic number, denoted as 'Z', is a fundamental property of an element and identifies the number of protons in the nucleus of an atom, which consequently defines the element itself. For instance, the atomic number of tantalum (Ta) is 73, indicating that a tantalum atom contains 73 protons. Similarly, oxygen (O) has an atomic number of 8, and sulfur (S) has an atomic number of 16.

The atomic number is significant not only in determining the element's identity but also in understanding the compound's composition. By knowing the atomic numbers, we could compute the total protons in a compound, which defines its nucleus. For \(\mathrm{Ta}_2 \mathrm{O}_5\), the total number of protons would be the sum of protons in tantalum and oxygen atoms involved. Substituting oxygen with sulfur changes the proton count due to sulfur's higher atomic number, thus subtly altering the properties of the compound.