Periodic Table

In STEM, we learned about the periodic table. Dmitri Mendeleev created the periodic table in 1869s. Why did he create it? Mendeleev was a chemist teacher. He was writing a chemistry textbook and he needs a way to organize the elements and it would be easier for the student to learn. Here are some facts about the periodic table:

  • Mendeleev used atomic mass instead of the atomic number because protons had not yet been discovered when he made his table
  • The symbol consists of one or two letters that come from the chemical name
  • The first letter is always written in UpperCase.
  • The second letter is always written in LowerCase.
  • The classes of elements are metals, metalloids, and nonmetals
  • Blue stands for metals, orange for metalloids, and green for nonmetals
  • Rows of the modern table are called period.
  • From left to right across a period, each element has one more proton than the element before it
  • The modern periodic table has 7 periods and 18 groups.

Just how small is an atom?

I love to study stem because it is very interesting. For our stem this year we learned about the family of atom. Our teacher introduced us to the atom families story:

In the center of Matterville, there is a place called the Nucleus Arcade, where two members of the Atoms Family like to hang out. Perky Patty Proton, like her sisters, is quite large with a huge smile and eyes that sparkle (+). Patty is always happy and has a very positive personality. Nerdy Nelda Neutron is large like Patty, but she has a boring, flat mouth and eyes with zero expression (o). Her family is very apathetic and neutral about everything. Patty, Nelda, and their sisters spend all their time at the arcade.

Around the Nucleus Arcade, you will find a series of roadways that are used by another member of the Atoms Family, Enraged Elliott Electron. Elliott races madly around the Arcade on his bright red chrome- plated Harley-Davidson. He rides so fast that no one can be sure where he is at any time. Elliott is much smaller than Patty and Nelda and he is always angry because these bigger relatives will not let him in the Arcade. He has a frown on his face, eyes that are squinted with anger, and a very negative (-) attitude.

The first energy street can only hold only two Electron brothers. The second energy street, called the Energy Freeway, can hold 8 brothers. The third energy street, called the Energy Superhighway, can hold 18 of the brothers.

The moral of Matterville is stable as long as each negative Electron brother is balanced out by one positive Proton sister. The number of residents in Matterville depends on the Proton and Neutron families.

We also learned about the different components of an atom that includes, electron, neutron, proton, and nucleus. It is very fascinating if you think about how small an atom really is. For example, the atom that is in grapefruit if you blow it to the size of a single blueberry, then the grapefruit would be as big as the Earth.  In stem class, I take note in my book instead of the computer. I also include drawing so that it can help understand more about the topic.

This is my note