Chemistry Tutorial: Atomic Structure meets the Periodic Table

like in the last video we're going to make different kinds of atoms by putting ten protons in the nucleus one at a time and as we do that we will place ten electrons in the electron shells outside the nucleus remember that we are simplifying our picture of the atom by not bothering about the neutrons at this stage we'll do that later we will also show how the atoms that we make fit into the periodic table let's see if there's a connection between the number of protons and electrons with the periodic tables shape adding one proton and one electron as we already have makes hydrogen atomic number one as we add more we build elements with bigger atomic numbers after adding 10 protons and 10 electrons we will have neon now let's start with a blank periodic table and add protons and electrons see if you can spot the connection because we're only making the first ten elements of the periodic table we only need the first few rows so let's zoom in on those we'll start from the beginning by making hydrogen again as we make the atoms on the Left we will put them into their position in the periodic table above one proton and one electron makes a hydrogen atom atomic number one now watch the rest you you you let's first look at where the protons in the nucleus show up on the periodic table with one proton we made the element with atomic number one hydrogen with two protons in the nucleus we made the element with atomic number two helium there's a simple connection between these numbers they're always the same the atomic number of an element is equal to the number of protons in the nucleus you can't get much simpler than that now let's look at where the electrons in their shells show up on the periodic table did you spot the connection between shells and rows when we filled the first electron shell we also filled the first row of the periodic table the first chill takes two electrons before it becomes full and the first row takes two elements when we filled the second shell we also filled the second row the second shell takes eight electrons before it becomes full and the second row takes eight elements can you guess how many electrons the third and fourth shells take before they become full according to our new theory the number of electrons that it takes to fill the third shell is the same as the number of elements in the third row of the periodic table let's count them one two three four five six seven eight the third shell can take eight electrons same as the second shell while we're at it let's count the fourth row 1 2 3 4 5 6 7 8 9 10 11 18 so it must take 18 electrons to fill the fourth shell does this agree with the experiment yes it does scientists have measured the number of electrons in each shell and this agrees with our answers to in the first shell eight in a second eight in the third and 18 in the fourth shell so how many electrons can the fifth sixth and seventh shells take see if you can work it out in the next video we will see how the electrons in the outer shell are the most important ones they tell the element how to behave that is what properties it will have such as color hardness electrical conductivity and so on they also tell the atom how it will join with other atoms and how many to join with the outer electrons are called the valence electrons and they're really cool

Channel: AtomicSchool

Views: 385,637

Keywords: Chemistry Tutorial, Atomic Structure, the periodic table, nucleus in shells, properties of elements, Atomic Number, protons, electrons, elements, online chemistry course, chemistry course, Nuclear Science, primary school, science students, atomic school, Ian stuart, Electrochemistry, science videos, atomic theory, chemistry class, high school, scientists, Australian schools, World Science Festival, genetics, electronics, nanotechnology

Id: 3_FJIpKgdV4

Length: 8min 17sec (497 seconds)

Published: Tue Nov 05 2013