Learn Chemistry - A Guide to Basic Concepts

Learn Chemistry - A Guide to Basic Concepts Chemistry is a logical science. You can master the essential concepts yourself. You can study these concepts in any order, but its probably best to start from the top and work your way down  since many concepts build on understanding units, conversion, and how atoms and molecules interact. Key Takeaways: How to Learn Chemistry Its possible to learn the basic concepts of chemistry online.Chemistry concepts should be studied in a logical order because concepts build upon each other. Jumping into the middle of the science can lead to confusion.While its fine to learn chemistry principles online, be aware that the lab component is an important part of the science. Its a good idea to supplement textbook learning with experiments using a chemistry kit. Introduction to Chemistry: Learn about what chemistry is, what chemists do, and why you would want to study this science.Units Measurements: Get a handle on the metric system and the common units used in chemistry.The Scientific Method: Scientists, including chemists, are systematic about the way they study the world. Find out how to use the scientific method to collect data and design experiments.The Elements: Elements are basic building blocks of matter. Learn what an element is and get facts for them.The Periodic Table: The periodic table is a way elements can be organized, based on their similar properties. Find out what that table is, how it was designed, and how you can use it to make your study of chemistry much easier.Atoms and Ions: Atoms are single units of an element. Ions can be made up of one or more types of elements and carry an electrical charge. Learn about the parts of an atom and how to identify the different types of ions.Molecules, Compounds, Moles: Atoms can b e joined together to make molecules and compounds. A mole is a useful way of measuring an amount of atoms or larger components of matter. Define these terms and learn how to perform calculations to express quantities. Chemical Formulas: Atoms and ions dont bond together randomly. Find out how to predict how many of one type of atom or ion will combine with others. Learn to name compounds.Chemical Reactions Equations: Just as atoms and ions combine in very specific ways, molecules and compounds react with each other in definite quantities. Learn how to tell whether or not a reaction can occur and what the products of a reaction will be. Write balanced chemical equations to describe reactions.Thermochemistry: Chemistry is the study of both matter and energy. Once you learn to balance the atoms and charge in a chemical reaction, you can examine the energy of the reaction as well.Electronic Structure: Electrons are found in regions around the nucleus of an atom. Learning about the structure of the electron shell or electron cloud is important for understanding how atoms and ions will form bonds.Chemical Bonds: The atoms in a molecule or compound are attracted and repelled with respect to each other i n ways that determine the types of bonds they can form. Molecular Structure: Once you understand the types of bonds that can be formed between components in a substance, you can begin to predict and understand how molecules are formed and the shapes they take. Valence shell electron pair repulsion (VSEPR) theory helps chemists understand molecular structure.Liquids Gases: Liquids and gases are phases of matter with properties distinctly different from the solid form. Collectively, liquids and gases are termed fluids. The study of fluids and how they interact is important for understanding the properties of matter and predicting the ways in which that matter can react.Rates of Reaction: Several factors affect how quickly and completely a reaction proceeds. Learn about these factors and how to calculate the speed at which a reaction can occur.Acids Bases: There are several ways to define acids and bases. One way is to look at hydrogen ion concentration. No matter which method you choose, these categories of chemicals participate in some v ery important reactions. Learn about acids, bases, and pH. Oxidation Reduction: Oxidation and reduction reactions go hand in hand, which is why they are also called redox reactions. Acids and bases may be thought of as reactions involving hydrogen or protons, while redox reactions tend to be concerned with electron gain and loss.Nuclear Reactions: Most chemical reactions involve exchanges of electrons or atoms. Nuclear reactions are concerned with what happens inside the nucleus of an atom. This includes radioactive decay, fission, and fusion.

Definition and Examples of Content (Lexical) Words

Definition and Examples of Content (Lexical) Words In English grammar and semantics, a  content word is a  word that conveys information in a text or speech act. Also known as a lexical word, lexical morpheme,  substantive category, or contentive.  Contrast with  function word  or grammatical word. In his book The Secret Life of Pronouns (2011), social psychologist James W. Pennebaker expands this definition: Content words are words that have a culturally shared meaning in labeling an object or action. . . . Content words are absolutely necessary to convey an idea to someone else. Content words- which include nouns, lexical verbs, adjectives, and adverbs- belong to open classes of words: that is, new members are readily added. The denotation of a content word, say  Kortmann and Loebner, is the category, or set, of all its potential referents (Understanding Semantics, 2014). Examples and Observations All morphemes can be divided into the categories lexical [content] and grammatical [function]. A lexical morpheme has a meaning that can be understood fully in and of itself- {boy}, for example, as well as {run}, {green}, {quick}, {paper}, {large}, {throw}, and {now}. Nouns, verbs, adjectives, and adverbs are typical kinds of lexical morphemes. Grammatical morphemes, on the other hand- such as {of}, {and}, {the}, {ness}, {to}, {pre}, {a}, {but}, {in}, and {ly}- can be understood completely only when they occur with other words in a sentence. (Thomas E. Murray, The Structure of English. Allyn and Bacon, 1995)Reverend Howard Thomas  was the presiding elder over a district in  Arkansas, which included  Stamps. (Maya Angelou,  I Know Why the Caged Bird Sings. Random House, 1969)Most people with low self-esteem have earned it. (George Carlin, Napalm Silly Putty. Hyperion, 2001)The  odor  of fish hung thick in the air. (Jack Driscoll,  Wanting Only to Be Heard. University of Massachusetts Press, 1995) Liberal and conservative have lost their meaning in America. I represent the distracted center. (Jon Stewart) Function Words vs. Content Words Grammatical words [function words] tend to be short: they are normally of one syllable and many are represented in spelling by less than three graphemes (I, he, do, on, or). Content words are longer and, with the exception of ox and American Englishs ax, are spelt with a minimum of three graphemes. This criterion of length can also be extended to the production of the two sets of words in connected speech. Here grammatical words are often unstressed or generally de-emphasised in pronunciation. (Paul Simpson, Language Through Literature. Routledge, 1997) All languages make some distinction between content words and function words.  Content words carry descriptive meaning; nouns, verbs, adjectives, and adverbs are types of content word. Function words are typically little words, and they signal relations between parts of sentences, or something about the pragmatic import of a sentence, e.g. whether it is a question. Lewis Carrolls Jabberwocky poem illustrates the distinction well: Twas brillig, and the slithy tovesDid gyre and gimble in the wabe:All mimsy were the borogoves,And the mome raths outgrabe. In this poem all the made-up words are content words; all the others are function words. In English, function words include determiners, such as the, a, my, your, pronouns (e.g. I, me, you, she, them), various auxiliary verbs (e.g. have, is, can, will do), coordinating conjunctions (and, or, but), and subordinating conjunctions (e.g. if, when, as, because). Prepositions are a borderline case. They have some semantic content, but are a small closed class, allowing hardly any historical innovation. Some English prepositions serve a mainly grammatical function, like of (what is the meaning of of?) and others have clear descriptive  (and relational) content, like under.  New content words in a language can  be readily invented; new nouns, in particular, are continually being coined, and new verbs (e.g. Google, gazump) and adjectives (e.g. naff, grungy) also not infrequently come into use. The small set of function words in a language, by contrast, is much more fixed and relatively steady over centuries. (James R. Hurford, The  Origins of Language: A Slim Guide.  Oxford University Press, 2014) Content Words in Speech Typically, the prominent syllable in a tone unit will be a content word (e.g. a noun or verb) rather than a function word (e.g. a preposition or article), since content words carry more meaning than function words. Function words will only be stressed if prominence on them is contextually warranted. (Charles F. Meyer, Introducing English Linguistics. Cambridge University  Press, 2010)