Problem 60 - Chemistry The Central Science In Si Units

Question

Fill in the blank with the appropriate numbers for both electrons and bonds (considering that single bonds are counted as one, double bonds as two, and triple bonds as three). (a) Iodine has valence electrons and makes ___________ bond(s) in compounds. (b) Silicon has ____________ valence electrons and makes _________ bond(s) in compounds. (c) Phosphorus has ___________ valence electrons and makes ________ bond(s) in compounds. (d) Sulphur has __________ valence electrons and makes __________ bond(s) in compounds.

Step-by-Step Solution

Answer

(a) Iodine has 7 valence electrons and makes 1 bond; (b) Silicon has 4 valence electrons and makes 4 bonds; (c) Phosphorus has 5 valence electrons and makes 3 bonds; (d) Sulphur has 6 valence electrons and makes 2 bonds.

Step 1: Understanding Valence Electrons and Bonds for Iodine

Iodine belongs to Group 17 (halogens) in the periodic table. Elements in this group have 7 valence electrons. Since iodine typically needs one more electron to complete its octet, it generally forms 1 bond.

Step 2: Finding Valence Electrons and Bonds for Silicon

Silicon is part of Group 14 in the periodic table. Elements in this group have 4 valence electrons. Silicon creates 4 bonds to satisfy the octet rule, as it can share these electrons with other atoms.

Step 3: Determining Valence Electrons and Bonds for Phosphorus

Phosphorus is in Group 15 of the periodic table, which means it has 5 valence electrons. In compounds, phosphorus usually makes 3 bonds; however, it can expand its octet and also form 5 bonds in certain molecules.

Step 4: Understanding Valence Electrons and Bonds for Sulphur

Sulphur is part of Group 16 and has 6 valence electrons. Sulphur typically forms 2 bonds when completing its octet, though it can form up to 6 bonds due to the availability of d-orbitals.

Key Concepts

Iodine Bonds

Iodine is an element found in Group 17 of the periodic table, also known as the halogens. Because it has 7 valence electrons, it seeks to gain that one extra electron to complete its octet. To achieve this, iodine often forms a single bond in compounds. This single bond allows iodine to attain a stable electron configuration.

In the context of chemical bonding, iodine's preference for forming one bond makes it quite predictable in its behavior. A common example of iodine forming a single bond is in molecules like hydrogen iodide (HI), where it pairs with a hydrogen atom to complete its valence shell. This results in a stable electron arrangement, crucial for maintaining chemical stability.

Silicon Bonds

Silicon is located in Group 14 of the periodic table. This group is characterized by having 4 valence electrons. Silicon's basic nature in forms bonds is rooted in its quest to fulfill the octet rule, which states that atoms are most stable when they have eight electrons in their valence shell.

To satisfy this rule, silicon forms four bonds. This is due to its ability to share each of its four valence electrons with other atoms. Consequently, silicon becomes a central player in forming complex compounds like silicon dioxide (SiO₂) and silicones. These silicon-based compounds are essential in materials science and a variety of technological applications due to their robust structural properties.

Phosphorus Bonds

Phosphorus is part of Group 15 and carries 5 valence electrons. This allows phosphorus to form three bonds under normal circumstances, aiming to mimic the stability observed in noble gases by fulfilling the octet rule.

Interestingly, phosphorus has the unique ability to expand its octet. In certain compounds, it can engage in five bonding instances by utilizing the available d-orbitals. This versatility is visible in compounds such as phosphorus pentachloride (PCl₅). Such a feature makes phosphorus incredibly versatile and crucial in a myriad of biological and chemical processes.

Sulphur Bonds

Situated in Group 16, sulfur possesses 6 valence electrons. Generally, sulfur is known to form 2 bonds by completing its octet to achieve stability. This can be seen in simple compounds like hydrogen sulfide (H₂S).

However, sulfur's chemistry doesn't stop there. It can form up to 6 bonds due to its available d-orbitals, making it capable of expanding its octet. This expansive bonding ability leads to the formation of more complex molecules like sulfur hexafluoride (SF₆). Such compounds are important in industrial applications due to their unique properties, which stem from sulfur's flexible bonding nature.