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Ch.4 Atoms and Elements
Timberlake - Chemistry: An Introduction to General, Organic, and Biological Chemistry 14th Edition
Timberlake14thChemistry: An Introduction to General, Organic, and Biological ChemistryISBN: 9781292472249Not the one you use?Change textbook
Chapter 4, Problem 103a,b

Provide the following:
a. the atomic number and symbol of the lightest alkali metal
b. the atomic number and symbol of the heaviest noble gas

Verified step by step guidance
1
Step 1: Recall the periodic table groups. Alkali metals are in Group 1, and noble gases are in Group 18.
Step 2: Identify the lightest alkali metal. The lightest alkali metal is hydrogen (H), but it is not typically classified as an alkali metal. The next lightest alkali metal is lithium (Li). Its atomic number is 3.
Step 3: Identify the heaviest noble gas. Noble gases are located in Group 18, and the heaviest noble gas is oganesson (Og). Its atomic number is 118.
Step 4: Write down the atomic number and symbol for lithium (Li) and oganesson (Og). Lithium has an atomic number of 3, and oganesson has an atomic number of 118.
Step 5: Verify your answers using the periodic table to ensure the atomic numbers and symbols are correct.

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Alkali Metals

Alkali metals are a group of elements found in Group 1 of the periodic table, characterized by their single valence electron, which makes them highly reactive. The lightest alkali metal is lithium, with an atomic number of 3 and the symbol 'Li'. These metals are known for their low density and are typically found in nature only in compound form.
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Noble Gases

Noble gases are located in Group 18 of the periodic table and are known for their lack of reactivity due to having a full valence shell of electrons. The heaviest noble gas is radon, which has an atomic number of 86 and the symbol 'Rn'. These gases are colorless, odorless, and exist in a gaseous state at room temperature.
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Atomic Number and Symbol

The atomic number of an element is the number of protons found in the nucleus of an atom, which determines the element's identity and its position in the periodic table. Each element is also represented by a unique chemical symbol, typically one or two letters derived from its name, such as 'Li' for lithium and 'Rn' for radon. Understanding these concepts is essential for identifying elements and their properties.
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