📚 Topic Summary
The periodic table isn't just a random arrangement of elements; it's organized to show repeating patterns in their properties. These patterns are called periodic trends. Key trends include atomic radius (size of the atom), ionization energy (energy needed to remove an electron), electronegativity (ability to attract electrons in a bond), and metallic character (how readily an atom loses electrons). These trends help us predict how elements will behave and react!
Understanding these trends can help you predict how different elements will react and what their properties might be. By grasping these fundamental concepts, you’ll be well-equipped to tackle more advanced chemistry topics.
🧪 Part A: Vocabulary
Match the terms with their correct definitions:
| Term |
Definition |
| 1. Ionization Energy |
A. The ability of an atom to attract electrons in a chemical bond. |
| 2. Electronegativity |
B. Half the distance between the nuclei of two identical atoms bonded together. |
| 3. Atomic Radius |
C. The energy required to remove an electron from a neutral atom in its gaseous phase. |
| 4. Metallic Character |
D. The measure of how easily an element loses electrons to form positive ions. |
| 5. Periodic Trend |
E. Specific patterns that are present in the periodic table which illustrate different aspects of a certain element. |
(Match the term number to the definition letter. Example: 1 - A)
⚛️ Part B: Fill in the Blanks
Complete the following paragraph using the words provided: increases, decreases, electronegativity, atomic radius, ionization energy.
As you move from left to right across a period, the ________ generally ________ because the nuclear charge increases, pulling the electrons closer to the nucleus. This also causes the ________ to increase, making it harder to remove an electron. Therefore, ________ generally ________ across a period. The ________ is the exception because metals tend to lose electrons easily.
🤔 Part C: Critical Thinking
Explain how the periodic trends help predict the reactivity of elements. Provide specific examples.