In this video about chemistry, I think the most important discovery is using electrons to explain the chemical bond. In 1916, Gilbert N. Lewis first proposed the concept of the covalent bond, which describes how atoms make up a molecule better than the theory of valence. Lewis supposed that electrons like to stay in pairs, and that they also like to keep the atom’s outer shell filled. So two atoms will share a pair, two pairs or three pairs of their valence electrons with each other. Atoms usually need 8 electrons to fill with their outer shell, but there are some exceptions, like hydrogen, which just needs 2 electrons. The pair of covalent electrons, is the so-called covalent bond. In 1919, based on the concept of covalent bond, Lewis …show more content…
He use this concept to make Lewis structures more powerful, because it can describes ions as well.
Drawing the Lewis structures of a compound is not very difficult. First we need to make sure how many lone pairs of electrons are in the outer shell form the periodic table. For example, carbon is in the 4A group, so it has 4 electrons and a positive kernel, which has a charge of positive 4. And then, it uses the electrons in the outer shell to form bonding pair with another atom’s valence electrons. When every atoms’ outer shell are fill with electrons, this is the Lewis structures of the molecule. Around the 1920s, quantum mechanics was gradually developed. And Schrödinger’s equation and molecule orbital theory can give the elections’ orbitals a more mathematical description. Nonetheless, some postulates and predictions made by Lewis are astonishingly accurate. Some predictions even helped the development of quantum theory. For instance, he predicted electrons like to stay in pairs, and lead to the discovery of a new quantum number, “spin”. Quantum mechanics also made Lewis structures more complete, solving the problem that a molecule sometimes has more than one Lewis structure. The concept of resonance was proposed and asserted that the actual structure is a hybrid. The resonance structures allow us
In 1801 President Thomas Jefferson asked Meriwether Lewis to act as his private secretary. Meriwether Lewis was a skilled frontiersman and an amateur scientist. Around 1804 Thomas Jefferson made Meriwether Lewis another offer, he asked him if he would led an expedition into the lands west of the Mississippi. Lewis asked one of his closet friend, William Clark, if he would join Lewis in this expedition; William Clark agreed to be his co-captain. Meriwether Lewis was an extraordinary man for the things he's accomplished as a frontiersman, amateur scientist, an intellectual and a explorer.
In "Energy Story" uses an explanation of atoms and tells us the parts of an atom and its structure. In the text it
J.J. Thompson didn’t really believe that the atom was the smallest piece to matter. So he did some experiments with running current through a glass tube with the air sucked out of it. That’s what a cathode ray tube is. It has a negative charge attached to the cathode (the metal piece farthest to the side of the tube) and the positive charge attached to the anode (the metal piece closer to the center of the tube). After running current through the cathode he realized that a stream of light was projected from the end that was being charged to the opposite and showing at the inside of the tube. He wasn’t very sure what it meant at first but then he figured it out.
I believe that C.S. Lewis is reasonable when he states that all men, women and children have “ some kind of Law or Rule of fair play or decent behaviour or morality.” I think this because, ever since we we born we were taught what is right and wrong. One may ask, “what is right or wrong, what is fair or unfair, what is just or unjust?” The answers, however, various from person to person, since our upbringing and experiences are different. For instance, a child born into a family were swearing was tolerated, may believe that swearing is like saying “hello”, an everyday normal word. A child born into a family that prohibited swearing, and punished for cursing, may believe that swearing is wrong. This is the predicament that most of us find our selfs in. For this reason, many of us quarrel not like animals, but in the human sense. C.S Lewis, claims that the “Law of Human Nature” is real and not a social construct. I agree with C.S Lewis since, a social construct changes with social views, and the Laws of Human Nature remain the same. A great examples of this is the Catholic Church. Roughly 60 years ago, Catholicism was extremely dominant; children, adults,
Linus Pauling was a creator with astounding intellectual abilities who was also active in many other areas as dictated by his interest and passion. His ideas and research into the nature of chemical bonds significantly changed the way that we understand the world.
Instead, early forms of the periodic table relied on using the physical properties of the elements known at that time. It must have been a great revelation to the chemists from the early part of this century to realise that there really was such a strong correlation between chemical properties of the elements and their physical structure. The periodic table. An example of a periodic table is given below : [IMAGE]
To think about all the time that went into composing a chart that can tell you about any atom around you is simply mind blowing. Not only was it necessary to organize all of the data but the data itself had to be uncovered. A simple table on a piece of laminated paper took hundreds of years of fine tuning and trial and error. That is what makes the periodic table so special and is why it should not be taken for granted.
This showed that dissolved gases were mechanically mixed with the water and weren?t mixed naturally. But in 1803 it was found that this depended on the weight of the individual particles of the gas or atoms. By assuming the particles were the same size, Dalton was able to develop the idea of atomic weights. In 1803 this theory was finalised and stated that (1) all matter is made up of the smallest possible particles termed atoms, (2) atoms of a given element have unique characteristics and weight, and (3) three types of atoms exist: simple (elements), compound (simple molecules), and complex (complex molecules).
Mendeleev later found himself working on a textbook for his students; Mendeleev goal was to demonstrate the relationship of 60 different elements. He began by writing down all the physical and chemical properties of each element on a note card and moved them around until he found an order that worked. Mendeleev arranged the elements in his periodic table in order of increasing atomic mass (chemistry book).
Stemming from the first years of the 20th century, quantum mechanics has had a monumental influence on modern science. First explored by Max Planck in the 1900s, Einstein modified and applied much of the research in this field. This begs the question, “how did Einstein contribute to the development and research of quantum mechanics?” Before studying how Einstein’s research contributed to the development of quantum mechanics, it is important to examine the origins of the science itself. Einstein took much of Planck’s experimental “quantum theory” research and applied it in usable ways to existing science. He also greatly contributed to the establishment of the base for quantum mechanics research today. Along with establishing base research in the field, Einstein’s discoveries have been modified and updated to apply to our more advanced understanding of this science today. Einstein greatly contributed to the foundation of quantum mechanics through his research, and his theories and discoveries remain relevant to science even today.
Dalton’s atomic theory says that each element contained its own number of atoms. Each element had its own size and weight. Dalton’s idea said that all things are made of small bits of matter this bits of matter where too small to be seen even with a microscope. Scientist began to think these small bits of matter where responsible for chemical changes. They thought that when these bits of matter combined a chemical change took place. Dalton assumed that there was a special pattern in the elements and was partly responsible for the periodic table.
To start off, learning the Bohr-Rutherford diagrams in grade nine was a very big confusion for me. I had never fully understood how many shells should go around the nucleus nor did I know how to do the many calculations. As I progressed into grade ten, the teachings became easier. The review shows an example such as in the the bohr diagram, a nucleus is in the center, which is a little circle, and following that there are shells surrounding it containing electrons. Each ring can only hold a certain amount of electrons, and so the first shell around the nucleus can hold a maximum of 2 electrons, the next shell is able to hold a maximum of 8 electro...
I feel personally that the discovery of the atom was an important discovery for the world. With the discovery we are now able to answer questions we never even thought to ask. We are also answering questions some people asked long ago. We can now use our vast knowledge of the atom to measure the stars and be able to tell you what the stars are made of. The atomic discovery also helped us find our periodic table of elements. The periodic table of elements is a huge scientific chart that shows important facts with the help of its formation. There was a lot of constant scientific research that went into making the periodic table of elements and what it is today.
... pattern of these resonance waves in order to cut down on interference, thus creating a richer sound.
From these properties of bonds we will see that there are two fundamental types of bonds--covalent and ionic. Covalent bonding represents a situation of about equal sharing of the electrons between nuclei in the bond. Covalent bonds are formed between atoms of approximately equal electronegativity. Because each atom has near equal pull for the electrons in the bond, the electrons are not completely transferred from one atom to another. When the difference in electronegativity between the two atoms in a bond is large, the more electronegative atom can strip an electron off of the less electronegative one to form a negatively charged anion and a positively charged cation. The two ions are held together in an ionic bond because the oppositely charged ions attract each other as described by Coulomb's Law.