Question

Identify each of the following as an acid, a base, or a salt, and give its name: a. \(\mathrm{LiOH}\) b. \(\mathrm{Ca}\left(\mathrm{NO}_{3}\right)_{2}\) c. HBr d. \(\mathrm{Ba}(\mathrm{OH})_{2}\) e. \(\mathrm{H}_{2} \mathrm{CO}_{3}\)

Short answer

a. Base, lithium hydroxide b. Salt, calcium nitrate c. Acid, hydrobromic acid d. Base, barium hydroxide e. Acid, carbonic acid

Step-by-step solution

Identify \(\mathrm{LiOH}\)

First, determine the components of \(\mathrm{LiOH}\). It contains lithium (Li) and hydroxide (OH). Compounds with hydroxide typically form bases. Thus, \(\mathrm{LiOH}\) is a base. The name of \(\mathrm{LiOH}\) is lithium hydroxide.

Identify \(\mathrm{Ca}\left(\mathrm{NO}_{3}\right)_{2}\)

Next, examine \(\mathrm{Ca}\left(\mathrm{NO}_{3}\right)_{2}\). It consists of calcium (Ca) and the nitrate ion \(\left(\mathrm{NO}_{3}\right)\). Nitrates are typically salts. Therefore, \(\mathrm{Ca}\left(\mathrm{NO}_{3}\right)_{2}\) is a salt. The name of \(\mathrm{Ca}\left(\mathrm{NO}_{3}\right)_{2}\) is calcium nitrate.

Identify HBr

Examine the compound HBr. It contains hydrogen (H) and bromine (Br). Hydrogen combined with a halogen (group 17 elements) typically forms an acid. Hence, HBr is an acid. The name of HBr is hydrobromic acid.

Identify \(\mathrm{Ba(OH)}_{2}\)

Now, look at \(\mathrm{Ba(OH)}_{2}\). It contains barium (Ba) and hydroxide (OH). Compounds with hydroxide are generally bases. Thus, \(\mathrm{Ba(OH)}_{2}\) is a base. The name of \(\mathrm{Ba(OH)}_{2}\) is barium hydroxide.

Identify \(\mathrm{H}_{2}\mathrm{CO}_{3}\)

Lastly, examine \(\mathrm{H}_{2}\mathrm{CO}_{3}\). It consists of hydrogen (H) and the carbonate ion \(\mathrm{CO}_{3}\). Because it contains hydrogen and a polyatomic ion, it is an acid. Therefore, \(\mathrm{H}_{2}\mathrm{CO}_{3}\) is an acid. The name of \(\mathrm{H}_{2}\mathrm{CO}_{3}\) is carbonic acid.

Key concepts

Acid-Base Chemistry

Acid-base chemistry is a crucial part of understanding chemical reactions. Acids are substances that release hydrogen ions (H⁺) when dissolved in water, while bases release hydroxide ions (OH^-).
A key point to remember is that acids typically have a pH less than 7, while bases have a pH greater than 7.
For example, HBr, which contains hydrogen, is an acid because it releases H⁺ ions in solution. On the other hand, \(\mathrm{LiOH}\), having hydroxide, is a base as it releases OH^- ions in solution.
\(\mathrm{Ba(OH)}_{2}\) and \(\mathrm{H_{2}CO_{3}}\) follow the same principles.

Knowing these basic principles will help you identify whether a compound is acidic or basic when interacting with other chemicals.

Inorganic Compounds

Inorganic compounds are minerals, salts, and metals that usually do not come from living organisms. They are formed almost always by elements other than carbon.
Unlike organic compounds, which contain significant amounts of carbon and hydrogen, inorganic compounds include various elements from the periodic table.
For example, \(\mathrm{Ca(NO_{3})_{2}}\) is an inorganic compound as it does not contain carbon.
Inorganic compounds can be categorized into different groups, such as acids, bases, salts, and neutral compounds.
Understanding the nature of inorganic compounds helps in grasping the concepts of chemical reactions, their properties, and their practical applications.

Nomenclature of Compounds

Nomenclature is the system of naming chemical substances. Different classes of compounds have unique naming rules.
For acids, if the compound consists of hydrogen and a halogen, the name typically ends with '-ic acid.' For instance, HBr is named hydrobromic acid.
For bases, the name usually includes the metal followed by 'hydroxide.' Therefore, \(\mathrm{LiOH}\) is called lithium hydroxide.
Salts are named by mentioning the metal first, then the non-metal or polyatomic ion. In this way, \(\mathrm{Ca(NO_{3})_{2}}\) is calcium nitrate.
Learning the systematic way of naming compounds ensures clarity and proper communication in the scientific community.

Chemical Classification

Chemical classification involves grouping substances based on their properties and chemical behavior.
Compounds can be divided into several categories: acids, bases, salts, and more.
Acids, like HBr and \(\mathrm{H_{2}CO_{3}}\), are substances that donate H⁺ ions when dissolved in water.
Bases, such as \(\mathrm{LiOH}\) and \(\mathrm{Ba(OH)_{2}}\), donate OH^- ions in aqueous solutions.
Salts form when acids and bases react together and usually consist of a metal cation and a non-metal or polyatomic anion.
For example, \(\mathrm{Ca(NO_{3})_{2}}\), includes the metal cation calcium (Ca²⁺) and the nitrate anion (NO₃^-).
Proper classification helps in predicting the properties of elements and understanding their interactions.