Difference Between Atomic Weight and Atomic Mass

Atomic weight and atomic mass are two important concepts in chemistry and physics. Many people use the terms interchangeably, but they dont actually mean the same thing. Take a look at the difference between atomic weight and atomic mass and understand why most people are confused or dont care about the distinction. (If youre taking a chemistry class, it could show up on a test, so pay attention!) Atomic Mass Versus Atomic Weight Uranium has two primordial isotopes (uranium-238 and uranium-235). Uranium-238 has 92 protons plus 146 neutrons and uranium-235 92 protons and 143 neutrons. Â  Pallava Bagla/Getty Images Atomic mass (ma) is the mass of an atom. A single atom has a set number of protons and neutrons, so the mass is unequivocal (wont change) and is the sum of the number of protons and neutrons in the atom. Electrons contribute so little mass that they arent counted. Atomic weight is a weighted average of the mass of all the atoms of an element, based on the abundance of isotopes. The atomic weight can change because it depends on our understanding of how much of each isotope of an element exists. Both atomic mass and atomic weight rely on the atomic mass unit (amu), which is 1/12th the mass of an atom of carbon-12 in its ​ground state. Can Atomic Mass and Atomic Weight Ever Be the Same? If you find an element that exists as only one isotope, then the atomic mass and the atomic weight will be the same. Atomic mass and atomic weight may equal each other whenever you are working with a single isotope of an element, too. In this case, you use the atomic mass in calculations rather than the atomic weight of the element from the periodic table. Weight Versus Mass: Atoms and More Mass is a measure of the quantity of a substance, while weight is a measure of how a mass acts in a gravitational field. On Earth, where we are exposed to a fairly constant acceleration due to gravity, we dont pay much attention to the difference between the terms. After all, our definitions of mass were pretty much made with Earth gravity in mind, so if you say a weight has a mass of 1 kilogram and a 1 weight of 1 kilogram, youre right. Now, if you take that 1 kg mass to the Moon, its weight will be less. So, when the term atomic weight was coined back in 1808, isotopes were unknown and Earth gravity was the norm. The difference between atomic weight and atomic mass became known when F.W. Aston, the inventor of the mass spectrometer (1927) used his new device to study neon. At that time, the atomic weight of neon was believed to be 20.2 amu, yet Aston observed two peaks in the mass spectrum of neon, at relative masses 20.0 amu and 22.0 amu. Aston suggested there two actually two types of neon atoms in his sample: 90% of the atoms having a mass of 20 amu and 10% with a mass of 22 amu. This ratio gave a weighted average mass of 20.2 amu. He called the different forms of the neon atoms isotopes. Frederick Soddy had proposed the term isotopes in 1911 to describe atoms that occupy the same position in the periodic table, yet are different. Even though atomic weight is not a good description, the phrase has stuck around for historical reasons. The correct term today is relative atomic mass — the only weight part of the atomic weight is that it is based on a weighted average of isotope abundance.

The History Of Moby Dick - 1791 Words

The History of Moby Dick On October 8th, 1851, the book â€Å"Moby Dick† written by Herman Melville was published, which be later be considered a Great American Epic. Melville before he was a writer took an a few odd occupations, including a banker, a teacher, and a whaler for about 5 years. On his voyages he heard many tales, one about a peculiar and catastrophic incident involving a certain whaling boat. â€Å"Moby Dick† based off of this tale, telling a story of a young man called Ishmael signs up to work on the ship the â€Å"Pequad†. The ship was captained by a strict, crazy man called Ahab, who would stop at nothing to kill Moby Dick, the white whale. At first, â€Å"Moby Dick† was poorly received. At first people hated it, a considered it to be one of Melville’s worst books. It wasn’t considered a â€Å"Great American Epic† until after Melville’s death. Today however, â€Å"Moby Dick† has been influential to other writers and literary topi cs, such as movies. One popular movie, not based off of â€Å"Moby Dick† but it’s true story, about Captain Pollard and his first mate Owen Chase, â€Å"The Heart of the Sea† stands out among the others. â€Å"The Heart of the Sea† was produced by Ron Howard, who says he wanted to create a â€Å"Moby Dick† movie, but instead told the actual story the book was based off of. â€Å"The Heart of the Sea†, is about the true story of â€Å"Moby Dick†, about a whale that attacks Captain Pollard s ship â€Å"the Essex†, sinking it and leaving the crew members stranded with three lifeboats, little food,Show MoreRelatedA Great Writer By Herman Melville904 Words   |  4 PagesIt is not everyday that a man is able to write himself into history, only the greatest and most daring writers are able to break the threshold of humanity and ascend into the history books. Growing up with two of the most influential grandfathers who were both Revo lutionary heroes, Herman Melville grew into a great writer. Bankruptcy and the loss of his father at age 12 had such a big impact on Herman that he was taken out of school and forced to work. He self-taught himself and briefly went backRead MoreHerman Melville s Moby Dick 1724 Words   |  7 PagesThe astonishing life of Herman Melville generated a great idea to create the novel Moby Dick. The historic point on Melville was very surprising and gothic. The author takes the view point and emotion towards the American Gothics. A heart warming personality, and a prosperous life influenced the writing of Moby Dick, and also helped launch the Gothic author Herman Melville into stardom, but Melville never got to see his fame come into reality in the fictional genre during the American RomanticismRead MoreHerman Melville Research Paper1644 Words   |  7 Pagesthat may cost friendships, possessions, and even lives. Revenge is often a major motivating factor in the characters that are in the works written during the Dark Romanticism period. One of the most celebrated and influential American authors in history, Herman Melville, was born on August 1, 1819; his reputation was not quite so illustrious during his lifetime, as most of his fame was gained posthumously. Herman Melville was born on August 1, 1819. His parents were quite wealthy so he did not haveRead MoreMoby Dick By Herman Melville1098 Words   |  5 Pages Moby Dick by Herman Melville is a tale of many things, and has become perhaps one of the most widely known revenge stories ever told, wherein the mad Captain Ahab chases the titular white whale to the ends of the earth, willing to sacrifice everything for revenge. The novel is known for its extensive symbolism and abstract or open-ended meaning. Many people find different meanings in the story, and the debate over what certain elements mean has been a point of contention since the novel was publishedRead MoreMoby Dick Themes1171 Words   |  5 PagesThemes Themes are the fundamental and often universal ideas explored in a literary work. The Limits of Knowledge As Ishmael tries, in the opening pages of Moby-Dick, to offer a simple collection of literary excerpts mentioning whales, he discovers that, throughout history, the whale has taken on an incredible multiplicity of meanings. Over the course of the novel, he makes use of nearly every discipline known to man in his attempts to understand the essential nature of the whale. Each of theseRead MoreMoby Dick, By John Steinbeck882 Words   |  4 PagesThis is exemplified in Moby dick, during which Ishmael goes on his long rant about different whales, â€Å"What am I that I should essay to hook the nose of this Leviathan! The awful tauntings in Job might well appeal to me. ‘Will he make a covenant with thee? Behold the hope of him is in vain!’ But I have swum through libraries and sailed through oceans; I have had to do with whales with these visible hands†(Melville ). This is Ishmael directly questioning his role when it comes to capturing the whaleRead MoreMelvilles Moby Dick: Comparing the Missions of Ahab and Ishmael1658 Words   |  7 PagesHerman Melville began working on this novel Moby Dick in 1850. In this book Melville challenges the relationship man have with his universe, his fate, and his God. Ahab represents a human being made up of evil, when he decides to questions God fate, and goes against God when he tries to strike Moby Dick the whale. The whale in this novel represents God. Moby-Dick, can teach you many things if you can remain focused long enough. However, the most important lesson that can be learned from the workRead MoreAnalysis Of Moby Dick By Herman Melville1276 Words   |  6 Pagesâ€Å"There is wisdom that is woe but there is a woe that is madness.†- Herman Melville. Moby-Dick is a novel that was written by Herman Melville, during the American Renaissance. Melville was an American novelist, short story writer, and a poet. Melville was influenced in his writing career by many people such as, William Shakesp eare (Macbeth, Romeo and Juliet), Nathaniel Hawthorne (The Scarlett Letter, The House of Seven Gables), and Edgar Allen Poe (The Raven, The Fall of the House of Usher). He wasRead MoreMoby Dick And Slavery As Its Parallel1526 Words   |  7 Pages Moby Dick and Slavery as its Parallel While the topic of slavery is never discussed explicitly in Herman Melville’s Moby Dick, racial disparities and Melville’s attitude towards them are portrayed both subliminally and prominently throughout the novel. By creating a parallel to the slave industry with the whaling industry, Melville is able to indirectly criticize the injustice of slavery. Moby Dick was published at a time where the country was on the brink of the Civil War and whaling and theRead MoreEssay about Herman Melvilles Moby-Dick1910 Words   |  8 PagesHerman Melvilles Moby-Dick   Ã‚  Ã‚  Ã‚  Ã‚  Herman Melville began working on his epic novel Moby-Dick in 1850, writing it primarily as a report on the whaling voyages he undertook in the 1830s and early 1840s. Many critics suppose that his initial book did not contain characters such as Ahab, Starbuck, or even Moby Dick, but the summer of 1850 changed Melville’s writing and his masterpiece. He became friends with author Nathaniel Hawthorne and was greatly influenced by him. He also read Shakespeare

The significance of this quote Free Essays

Nomi’s mother is never really developed within ‘A Complicated Kindness’ but is evidenced through Nomi’s reflections on her past life, a life that took her mother and sister from her. Nomi’s mother was excommunicated from the community in which she and her family lived. Quote 1 provides insight into how the plot will unfold by way of short sharp snippets of what, why, where and how things happen in Nomi’s life and her struggle to deal with the fate bestowed upon her. We will write a custom essay sample on The significance of this quote or any similar topic only for you Order Now The significance of this quote to the plot of the narrative is clear because it illustrates how Nomi would prefer to believe her mother was travelling which in reality cannot be so, for how can she be travelling without a passport. Such inference assumes that she is wandering aimlessly or maybe even dead – as dead as the ghost she appears to be in Nomi’s life. Only the â€Å"ID information† and a â€Å"black-and-white photo† are in the passport which again connotes a feeling of futility; we know Nomi’s mother existed or exists because the passport is provided in testimony of her being but that is all that is left of her existence other than memories for Nomi. The fact that the passport has no stamps or evidence of use helps to illustrate the life her mother lived; a life confined to one location, which was one of oppression and governed by rules. The photo provides confirmation for Nomi and readers that her mother, although living within the small community of Manitoba and possessing a passport never used, was hopeful of a better life, a life of travel and experience but a life that would never eventuate. The passport and its contents not only serve to carry forward the plot of Nomi’s story but also to provide evidence of her mother’s existence, the hope and dreams she desired and the stark reality that she was in fact now only a ghost in Nomi’s memories and reflections. He (Sheridan) said it gave him the creeps because that was where his mom had killed herself years ago? When it happened, years ago, Sheridan’s mom went nuts. Trudie had told me and Tash that she thought Sheridan’s dad should have left town to save his mom the pain of having to pretend he was dead. She’d really loved him. They’d had a lot of fun together when he wasn’t drunk (36-37). East Village Manitoba is a place filled with pretence, double standards, and secrecy. This quote is pertinent in that it reflects the irony evident in the lives of Manitoba’s community. We are told by way of a disjointed memory reflected upon by Nomi of how people living in Manitoba, more specifically in this case Sheridan and his family, live a lie. Sheridan’s father was a drunk but drank in secrecy in fear of being excommunicated from the town; his wife therefore rather than admit the truth pretended he was dead. Living a life of deceit caused Sheridan’s mother to go insane and commit suicide. The irony of being unhappy but shamming happiness is evident throughout the novel but this quote presages the futility and despair of living that lie. Both Sheridan’s mother and father achieved nothing from their pretence except pain and downfall, which in turn led to Sheridan’s plight of having to cope with his life without either parent. Nomi’s reference to her mother telling her and her sister Tash that they were once happy and in love serves to add more sentiment to the fact; the fact that living in a town full of oppression and rigidity in turn causes people to live a life of lies that has no ending other than misery. Through use of this quote and Nomi’s reflection we realize that living in fear of excommunication, people of Manitoba are forced to secrete what they do, but in doing so they are excommunicating themselves from their families, each other and most importantly themselves.    How to cite The significance of this quote, Papers

The significance of this quote Free Essays

Nomi’s mother is never really developed within ‘A Complicated Kindness’ but is evidenced through Nomi’s reflections on her past life, a life that took her mother and sister from her. Nomi’s mother was excommunicated from the community in which she and her family lived. Quote 1 provides insight into how the plot will unfold by way of short sharp snippets of what, why, where and how things happen in Nomi’s life and her struggle to deal with the fate bestowed upon her. We will write a custom essay sample on The significance of this quote or any similar topic only for you Order Now The significance of this quote to the plot of the narrative is clear because it illustrates how Nomi would prefer to believe her mother was travelling which in reality cannot be so, for how can she be travelling without a passport. Such inference assumes that she is wandering aimlessly or maybe even dead – as dead as the ghost she appears to be in Nomi’s life. Only the â€Å"ID information† and a â€Å"black-and-white photo† are in the passport which again connotes a feeling of futility; we know Nomi’s mother existed or exists because the passport is provided in testimony of her being but that is all that is left of her existence other than memories for Nomi. The fact that the passport has no stamps or evidence of use helps to illustrate the life her mother lived; a life confined to one location, which was one of oppression and governed by rules. The photo provides confirmation for Nomi and readers that her mother, although living within the small community of Manitoba and possessing a passport never used, was hopeful of a better life, a life of travel and experience but a life that would never eventuate. The passport and its contents not only serve to carry forward the plot of Nomi’s story but also to provide evidence of her mother’s existence, the hope and dreams she desired and the stark reality that she was in fact now only a ghost in Nomi’s memories and reflections. He (Sheridan) said it gave him the creeps because that was where his mom had killed herself years ago? When it happened, years ago, Sheridan’s mom went nuts. Trudie had told me and Tash that she thought Sheridan’s dad should have left town to save his mom the pain of having to pretend he was dead. She’d really loved him. They’d had a lot of fun together when he wasn’t drunk (36-37). East Village Manitoba is a place filled with pretence, double standards, and secrecy. This quote is pertinent in that it reflects the irony evident in the lives of Manitoba’s community. We are told by way of a disjointed memory reflected upon by Nomi of how people living in Manitoba, more specifically in this case Sheridan and his family, live a lie. Sheridan’s father was a drunk but drank in secrecy in fear of being excommunicated from the town; his wife therefore rather than admit the truth pretended he was dead. Living a life of deceit caused Sheridan’s mother to go insane and commit suicide. The irony of being unhappy but shamming happiness is evident throughout the novel but this quote presages the futility and despair of living that lie. Both Sheridan’s mother and father achieved nothing from their pretence except pain and downfall, which in turn led to Sheridan’s plight of having to cope with his life without either parent. Nomi’s reference to her mother telling her and her sister Tash that they were once happy and in love serves to add more sentiment to the fact; the fact that living in a town full of oppression and rigidity in turn causes people to live a life of lies that has no ending other than misery. Through use of this quote and Nomi’s reflection we realize that living in fear of excommunication, people of Manitoba are forced to secrete what they do, but in doing so they are excommunicating themselves from their families, each other and most importantly themselves.    How to cite The significance of this quote, Papers