Question

The chemical formula for zinc oxide is \(\mathrm{ZnO}\). Predict the formulas for each of the following similar compounds: (a) cadmium oxide (b) cadmium sulfide (c) cadmium selenide (d) cadmium telluride

Short answer

(a) CdO, (b) CdS, (c) CdSe, (d) CdTe.

Step-by-step solution

Understanding Zinc Oxide

The chemical formula for zinc oxide is ZnO, where zinc (Zn) has a charge of +2 and oxide (O) has a charge of -2. The charges need to balance each other for the compound to be neutral.

Similar Compound Analysis

For compounds involving cadmium, recognize that cadmium (Cd) is similar to zinc (Zn) in that it typically has a charge of +2.

Predicting Cadmium Oxide Formula

Cadmium oxide is similar to zinc oxide. Cadmium has a charge of +2 and oxide has a charge of -2, so their charges balance to form CdO.

Predicting Cadmium Sulfide Formula

For cadmium sulfide, since sulfur (S) typically has a -2 charge, cadmium (Cd) having a +2 charge will balance this, resulting in the formula CdS.

Predicting Cadmium Selenide Formula

Cadmium selenide involves cadmium (Cd) with a +2 charge and selenium (Se) with a -2 charge. The charges balance, so the formula is CdSe.

Predicting Cadmium Telluride Formula

In cadmium telluride, cadmium (Cd) has a +2 charge and tellurium (Te) has a -2 charge. The charges balance to give the formula CdTe.

Key concepts

Zinc Oxide

Zinc oxide, with its chemical formula \( \mathrm{ZnO} \), is a well-known compound commonly used in a variety of applications. The key feature of zinc oxide is its neutral charge, achieved by the balance of charges between its constituents. Zinc (\( \mathrm{Zn} \)) typically carries a +2 charge, while oxygen (\( \mathrm{O} \)) carries a -2 charge. Together, these charges neutralize each other, resulting in a stable compound.

Applications of zinc oxide stretch across multiple industries—from acting as a protective agent in sunscreens to serving as a catalyst in rubber production. Its ability to balance charges effectively makes it a valuable compound in many chemical reactions and products.

Cadmium Compounds

Cadmium compounds behave similarly to zinc compounds due to their comparable chemical properties. Cadmium (\( \mathrm{Cd} \)) shares an oxidation state of +2, just like zinc. This characteristic allows cadmium to form stable compounds with elements from group 16 of the periodic table, such as oxygen, sulfur, selenium, and tellurium.

Some significant cadmium compounds include:

• Cadmium oxide (\( \mathrm{CdO} \)), a common precursor in cadmium-based materials.
• Cadmium sulfide (\( \mathrm{CdS} \)), notable for its use in photovoltaic cells and pigments.
• Cadmium selenide (\( \mathrm{CdSe} \)), used primarily in semiconductors and quantum dots.
• Cadmium telluride (\( \mathrm{CdTe} \)), widely applied in solar panel technology.

Despite their utility, cadmium compounds should be handled with care due to their potential toxicity and environmental impact.

Charge Balancing

Charge balancing is a crucial concept in chemistry that ensures the stability of a compound. For a compound to be electrically neutral, the positive and negative charges from its components must equate.

Taking cadmium oxide (\( \mathrm{CdO} \)) as an example, cadmium's +2 charge complements the -2 charge of oxygen, resulting in a neutral compound. Similarly, in cadmium sulfide (\( \mathrm{CdS} \)), cadmium’s +2 charge balances sulfur’s -2 charge, also making it electrically neutral.

Charge balancing is essential in predicting the chemical formulas of compounds, especially when involving transition metals. A clear understanding of charge balancing helps to form an accurate chemical representation of compounds, thus aiding in the study or engagement with chemical reactions.

Chemical Nomenclature

Chemical nomenclature is the systematic naming of chemical compounds based on their composition and structure. It follows specific rules to create universally understood names for chemical substances. In the context of the compounds discussed, the names follow a straightforward pattern.

The nomenclature for simple binary compounds, such as those formed by cadmium and non-metals, includes:

• The name of the metal written first, followed by the non-metal with its suffix '-ide.'
• For example, cadmium oxide is named with 'cadmium' followed by 'oxide,' reflecting the presence of oxygen.

Understanding the basics of chemical nomenclature not only helps in writing formulas accurately but also assists in deciphering the properties and potential reactions of the compounds. Proper naming also facilitates effective communication in scientific contexts, ensuring clarity and precision.