14. Structure and Patterns in Periodic Table of Elements.pptx

The Periodic Table of Elements is a chart that organizes all known chemical elements according to their atomic number, electron configuration, and repeating chemical properties. It shows clear patterns and structures that help scientists understand how elements behave.

1. Structure and Patterns in PERIODIC TABLE of ELEMENTS

2. Understanding Periods and Groups Periodic Table is like a map of all known elemnts in the universe, organized in a way that helps us understand how each elements behave and interacts. To make sense of this map, let us explore two key ideas: Periods and Groups.

3. GROUPS These are the vertical columns in the Periodic Table. There are 18 groups in total. Elements in the same group have the same number of valence electrons. These valence electrons play a major role in determining how an element will react with others.

4. GROUPS Similar Chemical Properties - Elements within a group often have similar properties and react in similar ways. Shared Valence Electrons - Elements in the same group have the same number of valence electrons. For example, all elements in Group 2 have two valence electrons which makes them behave similarly in chemical reactions.

5. GROUPS Element Families - Some groups are known by special names because they include elements that behave similarly: a. Group 1 or A: Alkali Metals - They are very reactive, especially with cold water. b. Group 2 or IIA: Alkaline Earth Metals - Also reactive but less so than alkali metals

6. GROUPS c. Group 3 to 12: Transition Metals - They occupy the middle portions of the long periods of the periodic table of elements between the groups on the left-hand side and the groups on the right. - Some make catalysts and are found in enzymes and other biomolecules, like hemoglobin and chlorophyll.

7. GROUPS d. Inner Transition Metals - The two series of elements that are 4f and 5f series known as Lanthanoids and Actinoids - They are providing good sources of Nuclear Energy.

8. GROUPS e. Group 13 or IIIA: Boron Group - They are characterized as a grouyp by having 3 electrons in the outermost part of their atomic structure. f. Group 14 or IVA: Carbon Group - Namely Carbon, Silicon, Germanium, Tin, Lead, and Flerovium.

9. GROUPS g. Group 15 or VA: Nitrogen Group - Consists of nitrogen, phosphorus, arsenic, astimony,, bismuth, and moscovium h. Group 16 or VIA: Oxygen or Chalcogens Group - Namely oxgen, sulfur, selenium, tellurium, polonium, livermorium.

10. GROUPS i. Group 17 or VIIA: The Halogen Elements - Consists of flourine, chlorine, bromine, iodine, astatine and tenessine. - They were given the name halogen, from the Greek roots “hal” means salt and “gen” means to produce because they all produce sodium salts of similar properties. - Halogens are highly reactive nonmetals.

11. GROUPS j. Group 18 or VIIIA: Noble Gases - They include helium, neon, argon, krypton, xenon, radon and oganesson. - The noble gases are colourless, odourless, tasteless, nonflammable gases. - Very unreactive because their outer electron of their outer electron shells are full.

12. PERIODS Increasing Atomic Number - As you move from left to right across aperiod, each element has one more electron than the element before it. Gradual Change in Properties - Elements change gradually across a period, from metals on the left side to non-metals on the right side.

13. PERIODS Addition of Electron Shells in New Periods - Each new period begins with an element that has en extra electron shell compared to the previous period. For example, elements in Period 2 have two electron shells, while those in period 3 have three electrons

14. ELECTRON STRUCTURE - Electrons occupy regions around the nucleus called electron shells. - These are also called energy levels because each electron shell corresponds to a particular energy. - The way the electrons of an atom are distributed in the various energy levels or electron shells is called Electronic Configuration.

15. ELECTRON STRUCTURE - The outer most shell is known as the valence shell , and the elctrons found in it are called valence electrons. - In general, atoms are most stable, least reactive, when their outermost electron shell is full. - Most of the elements need eight electrons in their outermost shell in order to be stable, and this rule is kown as the octet rule.

16. ELECTRON STRUCTURE - In the periodic table, a group is represented by a vertical column. The number of Electrons in the outermost shell is the valence electron for each group.