The following ionic compounds are found in common household products. Write the formulas for each compound: (a) potassium phosphate (b) copper(II) sulfate (c) calcium chloride (d) titanium dioxide (e) ammonium nitrate (f) sodium bisulfate (the common name for sodium hydrogen sulfate)

Chemical nomenclature is the systematic naming of chemical compounds that allows chemists and students to communicate with clarity and precision about chemical formulas. Understanding chemical nomenclature starts with recognizing the elements and the numbers of atoms of each element in a compound. Ionic compounds are named based on the cation (positive ion) followed by the anion (negative ion). For instance, 'potassium phosphate' is composed of potassium ions (K⁺) and phosphate ions (PO₄³⁻).

When dealing with transition metals, like copper in 'copper(II) sulfate', the Roman numeral indicates the charge of the metal cation. The (II) in copper(II) tells us that copper has a +2 charge in this compound. Similarly, for compounds like 'calcium chloride', we derive the names directly from the constituent ions - 'calcium' for Ca²⁺ and 'chloride' from Cl⁻. In the case of 'titanium dioxide', the non-metal ion's name is changed to end with '-ide', signifying the inclusion of oxygen as 'oxide'.

Polyatomic ions are charged entities composed of two or more atoms covalently bonded, which function as a single ion in compounds. Understanding these ions is crucial for writing correct formulas of ionic compounds. For example, phosphate (PO₄³⁻) is a common polyatomic ion consisting of one phosphorus atom bonded to four oxygen atoms, carrying a net charge of -3. Sulfate (SO₄²⁻) is another typical polyatomic ion with sulfur surrounded by four oxygen atoms, bearing a -2 charge.

Ammonium (NH₄⁺) is a unique cationic polyatomic ion made up of one nitrogen atom covalently bonded to four hydrogen atoms, with an overall positive charge. Recognizing common polyatomic ions like these allows for the correct assembly of the ionic compound's formula, such as ammonium nitrate (NH₄NO₃), where ammonium and nitrate ions combine in a one-to-one ratio because of their matching charges.

Balancing ionic charges is a fundamental concept in creating the chemical formulas for ionic compounds. The principle of charge balance requires that the total positive charge from the cation(s) equals the total negative charge from the anion(s) in an ionic compound. For instance, when combining calcium (Ca²⁺) with chloride (Cl⁻) to form 'calcium chloride', two chloride ions are needed to balance the +2 charge of a single calcium ion, leading to the formula CaCl₂.

In the case of 'sodium bisulfate' (sodium hydrogen sulfate), recognizing that you have three ions (Na⁺ for sodium, H⁺ for hydrogen, and SO₄²⁻ for sulfate) and balancing their charges is essential. Ultimately, the correct formula is NaHSO₄, where both sodium and hydrogen contribute a total positive charge of +2, which is countered by the -2 charge of the sulfate ion. Balancing ionic charges allows us to avoid errors and predict the ratios of ions in the chemical formula of the compound.