Question

Identify the group \(1 \mathrm{~B}\) element in period five and the group \(2 \mathrm{~A}\) element in period four.

Short answer

Silver (Ag) is the Group 1B element in Period 5; Calcium (Ca) is the Group 2A element in Period 4.

Step-by-step solution

Understand the Periodic Table Group and Period Notations

The periodic table is arranged in rows called periods and columns called groups or families. Group 1B elements correspond to Group 11 (using IUPAC notation) and Group 2A corresponds to Group 2. Elements in different periods have their periods coincide with rows numbered from top to bottom starting at 1.

Identify the Group 1B Element in Period Five

Group 1B elements are the coinage metals: copper (Cu), silver (Ag), and gold (Au). The element in Period 5 from Group 1B is silver (Ag).

Identify the Group 2A Element in Period Four

Group 2A elements are alkaline earth metals: beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra). The element in Period 4 from Group 2A is calcium (Ca).

Verify Your Answers

From Step 2, the Group 1B element in Period 5 is silver (Ag), and from Step 3, the Group 2A element in Period 4 is calcium (Ca). Ensure these align with the periodic table positions as cross-referencing.

Key concepts

Groups and Periods

The periodic table is an amazing organizational tool used in chemistry to classify all known elements. Its structure is both logical and informative, providing a map for understanding elements' properties. The table is arranged into horizontal rows called "periods." Each period signifies a principal energy level that electrons occupy in an atom. From top to bottom, the periods are numbered starting from 1 to 7.

Vertical columns in the table are referred to as "groups" or "families." Groups are numbered either using Roman numerals and letters (like 1A or 1B), or using a modern IUPAC system, which numbers them from 1 to 18. Elements within the same group typically exhibit similar chemical properties because they have the same number of valence electrons. Understanding this aspect of the periodic table is essential to predicting element behavior and reactivity.

• For example, Group 1B (also Group 11 in the IUPAC system) includes metals known for their excellent conductivity and malleability.
• Meanwhile, Group 2A (Group 2) consists of the alkaline earth metals, characterized by their reactivity and presence in the earth's crust.

Coinage Metals

Coinage metals are a term that refers to a specific group of metals primarily used historically to mint coins. These metals are copper (\(\text{Cu}\)), silver (\(\text{Ag}\)), and gold (\(\text{Au}\)). They belong to Group 11 on the periodic table, also denoted as 1B in traditional grouping systems. Coinage metals are particularly notable for the following properties:

• High electrical conductivity - making them ideal for electrical wiring and circuits.
• Malleable and ductile - allowing them to be shaped into thin sheets and wires without breaking.
• Corrosion resistance - especially gold, which remains untarnished over time.

These metals are more than just currency; they play significant roles in electronics, jewellery, and even in certain industrial applications. In the context of the periodic table, they show the unique attributes of transition metals, combining metallic properties with stability, enhancing their value beyond mere monetary exchange.

Alkaline Earth Metals

Alkaline earth metals comprise Group 2 on the periodic table, equivalent to Group 2A in some notations. This group includes beryllium (\(\text{Be}\)), magnesium (\(\text{Mg}\)), calcium (\(\text{Ca}\)), strontium (\(\text{Sr}\)), barium (\(\text{Ba}\)), and radium (\(\text{Ra}\)). These elements share several key characteristics:

• They are all shiny, silvery-white metals.
• Highly reactive, especially with water, albeit less so than alkali metals.
• Their compounds often impart distinct colors to flames, making them useful in pyrotechnics (e.g., strontium compounds produce red flames).

Alkaline earth metals play vital roles in industry and biological systems. Calcium and magnesium, for instance, are essential to life on earth, critical in bone structure and enzyme function. These metals' versatility and reactivity make them indispensable in both natural and manufactured processes.