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22 Cards in this Set
- Front
- Back
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What is an atom, and where does the word atom come from?
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Atoms are tiny structures that can not be seen by the naked eye, you have to use a very powerful microscope.It is the smallest unit of matter, is uncuttable, and is the building blocks of matter. The word atom evolved from the Greek word atomos, which means uncuttable.
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What are elements, what is the Law of Definite composition, who created it, and when?
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An element is a substance that is made of one type of atom; it is pure.All the atoms are the same, and if you cut it into a really small piece, that would be the same atoms as the larger piece.If you have a oxygen atom at the north pole, it would be the same if it was in the Sahara desert.That is the Law of Definite Composition created in 1799 by Joseph Proust
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What is a chemical symbol, and give examples.
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A chemical symbol is a symbol that represents an element's name. Some seem to make sense, like Oxygen is O and helium is He, and some not, like gold is Au.Some of these strange names come from Latin or Greek. The Latin word for gold is aurum.Some are named after people or places, like californium and einsteinium.
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What is a nucleus?
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A small, but very dense center of the atom
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What is a proton?
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A positively charged part of an atom that makes up the nucleus.
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What is a neutron?
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A neutral part of an atom that makes up the nucleus.
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What is an electron
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An electron is a negatively charged
part of an atom that surrounds the nucleus.It is the lightest part of the atom. |
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Who invented the Law of Definite Composition?
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Joseph Proust
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List the different types of models of atoms in order.
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the Dalton model,the Thomson model, the Rutherford model, the Bohr or planetary model, the Electron Shell model. The model that scientists use today is called the Electron Cloud model.
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What is the Dalton model of the atom?
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The Dalton Model was where Dalton proposed the existence of the atom created in 1803, and that atoms of a substance are different from atoms of another substance.
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What is the Thomson model?
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The second model was called the Thomson model, where Thomson proposed the existence of electrons, negatively charged parts of the atom.
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What is the Rutherford model?
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The third model was called the Rutherford model, where Rutherford proposed the positively charged nucleus in the atom, but kept the electrons.
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What is the Bohr model?
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The fourth model was called the Bohr, or planetary model, where Bohr proposed that atoms move around the nucleus like planets move around the sun.
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What is the electron shell model?
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The fifth model is called the Electron Shell model, which shows that electrons move around the nucleus in levels, or "shells", and also has a neutron and proton.
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What is the Electron Cloud Model?
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The model that scientists use today is called the Electron Cloud model.It shows electrons in a area, or "cloud", and the exact location of the electron can not be found.
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What are molecules?Give an Ex.Can there be 2 of the same type of atom in a molecule?Explain.
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Molecules are two or more elements joined together.A molecule is made of either 2 or more like or unlike atoms, and is the smallest particle of a substance.Oxygen is made of 2 like oxygen atoms
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What is salt, it's symbol, and Explain.
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Salt is NaCl, and is made of chlorine (Cl), and sodium (Na). Even though these are poisonous, the end is commonly eaten.
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How can scientists understand atoms when you can not see them?
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We observe atoms on a large scale, so we can understand atoms on a small scale.Even though we do not see the atoms on the small scale, we can infer what is happening on the small scale by observing the atoms reaction on a large scale.
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How many elements are there, and how many are natural?
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There are more than 100 known elements,and more than 92 are natural.
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What is lead and iron's chemical symbol?
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Lead : Plumbrem : Pb
Iron : Ferrum : Fe |
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What are compounds?
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A compound is formed when two unlike atoms are combined.Water is made of 1 oxygen atom and 2 hydrogen atoms.Properties of a compound are different then the properties of the individual element.
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How does the law of definite composition apply to compounds? Give an example
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All samples of the same compound contain the same elements in the same proportion by mass.For ex: CO2=1 carbon + 2 Oxygen.The mass of carbon =12 and oxygen = 8.So the proportion of carbon to oxygen by mass is 12 to 16 or reduced 3 to 4.
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