![How to learn 1 to 20 elements of periodic table | easy way to learn 1 to 20 elements | class 9 & 10 - YouTube How to learn 1 to 20 elements of periodic table | easy way to learn 1 to 20 elements | class 9 & 10 - YouTube](https://i.ytimg.com/vi/KoINcCyq3X8/maxresdefault.jpg)
How to learn 1 to 20 elements of periodic table | easy way to learn 1 to 20 elements | class 9 & 10 - YouTube
![SOLVED: These are the first 20 elements on the periodic table. Which of these elements had 20 protons in its nucleus (atomic number = 12)? 1. He 2. S 3. Mg 4. SOLVED: These are the first 20 elements on the periodic table. Which of these elements had 20 protons in its nucleus (atomic number = 12)? 1. He 2. S 3. Mg 4.](https://cdn.numerade.com/ask_images/81f8d38ddfeb413a95517912c52a59ca.jpg)
SOLVED: These are the first 20 elements on the periodic table. Which of these elements had 20 protons in its nucleus (atomic number = 12)? 1. He 2. S 3. Mg 4.
![Which elements of the periodic table forming covalent bonds relate to psition and electron configuration Doc Brown's chemistry revision notes Which elements of the periodic table forming covalent bonds relate to psition and electron configuration Doc Brown's chemistry revision notes](https://docbrown.info/page04/4_71atom/PTelectrons.gif)