Give the symbol of the element that has the
b. largest atomic size in Period 4

Verified step by step guidance

1. Identify the elements in Period 4 of the periodic table. Period 4 includes elements from potassium (K) to krypton (Kr).
2. Recall the trend for atomic size across a period. Atomic size decreases from left to right across a period due to the increasing nuclear charge, which pulls the electrons closer to the nucleus.
3. Determine which element is located at the far left of Period 4. This element will have the largest atomic size because it has the fewest protons and the least effective nuclear charge pulling on its electrons.
4. Find the symbol of the element at the far left of Period 4. This element is potassium (K).
5. Conclude that the element with the largest atomic size in Period 4 is potassium (K).

Key Concepts

Atomic Size

Atomic size, or atomic radius, refers to the distance from the nucleus of an atom to the outermost shell of electrons. It generally increases down a group in the periodic table due to the addition of electron shells, while it decreases across a period from left to right due to increased nuclear charge, which pulls electrons closer to the nucleus.

Periodic Table Trends

The periodic table exhibits specific trends in atomic size, ionization energy, and electronegativity. In Period 4, elements are arranged in order of increasing atomic number, and understanding these trends helps predict the properties of elements, including which has the largest atomic size based on its position in the period.

Group vs. Period

In the periodic table, a group is a vertical column that contains elements with similar chemical properties, while a period is a horizontal row. Elements in the same group often have similar atomic sizes, but the largest atomic size in a specific period is typically found at the leftmost side, where the elements have fewer protons and a weaker pull on their outer electrons.