Easy Method to Prepare a Chemical Solution

Easy Method to Prepare a Chemical Solution Heres a quick overview of how to prepare a solution when the final concentration is expressed as M or molarity. You prepare a solution by dissolving a known mass of solute (often a solid) into a specific amount of a solvent. One of the most common ways to express the concentration of the solution is M or molarity, which is moles of solute per liter of solution. Example of How to Prepare a Solution Prepare 1 liter of 1.00 M NaCl solution. First, calculate the molar mass of NaCl which is the mass of a mole of Na plus the mass of a mole of Cl or 22.99 35.45 58.44 g/mol Weigh out 58.44 g NaCl.Place the NaCl in a 1-liter volumetric flask.Add a small volume of distilled, deionized water to dissolve the salt.Fill the flask to the 1 L line. If a different molarity is required, then multiply that number times the molar mass of NaCl. For example, if you wanted a 0.5 M solution, you would use 0.5 x 58.44 g/mol of NaCl in 1 L of solution or 29.22 g of NaCl. Important Points to Remember Molarity is expressed in terms of liter of solution, not liters of solvent. To prepare a solution, the flask is filled to the mark. In other words, it is incorrect to a 1 liter of water to a mass of sample to prepare a molar solution.Sometimes its necessary to adjust the pH of a solution. To do this, add enough water to dissolve the solute. Then add an acid or base solution dropwise (usually a hydrochloric acid or HCl solution for acid or sodium hydroxide or NaOH solution for a base) to reach the desired pH. Then add more water to reach the mark on the glassware. Adding more water wont change the pH value.

Examples of Diacritical Marks

Examples of Diacritical Marks In phonetics, a diacritical mark is a  glyph- or symbol- added to a letter that alters its sense, function, or pronunciation. It is also known as a diacritic or an accent mark. A  diacritical mark is a point, sign, or squiggle added or attached to a letter or character to indicate appropriate stress, special pronunciation, or unusual sounds not common in the Roman alphabet, according to  L. Kip  Wheeler, a professor at Carson-Newman University in Tennessee. Purpose While diacritical marks are more common in foreign languages, you do encounter them quite often in English. For example, diacritics are often used with  certain French loanwords,  words  that are imported into one  language  from another language. Cafà © and clichà ©Ã‚  are loanwords  from French that contain a diacritical mark called an acute accent, which helps indicate how the  final  e  is pronounced. Diacritical marks are used in dozens of other foreign languages, including  Afrikaans, Arabic, Hebrew,  Filipino, Finnish, Greek, Galician, Irish, Italian, Spanish, and Welsh. These marks can change not only the pronunciation but also the meaning of a word. One example in English is rà ©sumà © or resumà © versus resume. The first two terms are nouns that mean  curriculum vitae, while the second is a verb meaning to return to or begin again.   Diacritical Marks in English There are literally dozens of diacritical marks, but it is helpful to learn the basic diacritics in English, as well as their functions. Some of the marks and explanations are adapted from a  list of diacritical marks  created by Professor Wheeler. Diacritical Mark Purpose Examples Acute accent Used with certain French loanwords cafà ©, clichà © Apostrophe * Indicates possession or the omission of a letter children's, don't Cedilla Attached to the bottom of the letter c in French loanwords, indicating a soft c faà §ade Circumflex accent Indicates reduced primary stress à ©levtor à ´pertor Diaeresis or Umlaut Used with certain names and words as a guide to pronunciation Chloà «, Brontà «, coà ¶perate, naà ¯ve Grave accent Occasionally used in poetry to indicate that a normally silent vowel should be pronounced learnà ¨d Macron or Stress Mark A dictionary notation to signify "long" vowel sounds pÄ dÄ  for payday Tilde In Spanish loan words, the tilde indicates a /y/ sound added to a consonant. caà ±on or pià ±a colada Tilde In Portuguese loanwords, the tilde indicates nasalized vowels. So Paulo *Because marks of punctuation arent added to letters, theyre generally not regarded as diacritics. However, an exception is sometimes made for apostrophes. Examples of Diacritics Diacritical marks are plentiful in English-language articles and books. Writers and  lexicographers  have used the marks to great advantage over the years as these examples show: Acute accent:  Feluda handed over the blue  attachà © case  before he sat down.- Satyajit Ray, The Complete Adventures of Feluda Apostrophe: Lets go down to my house and have some more fun,  Nancy said. Mother wont let us, I said. Its too late now. Dont bother her, Nancy said.- William Faulkner, That Evening Sun Go Down. The American Mercury, 1931 Diaeresis  or Umlaut:  Five young activists were voted into office, bringing political validation to a youth-driven movement dismissed by establishment elders as naà ¯ve, unschooled, and untenable.- Youthquake. Time,   Oct. 6, 2016 Grave accent:  Margret stood in her chamber;Shed sewn a silken seam.She lookà ¨d east an she lookà ¨d west,An  she saw those woods grow green.Tam Lin, The Traditional Tunes of the Child Ballads Macron: neighbornoun  Ã‚  neigh ·bor   \ˈnÄ -bÉ™r\- Merriam-Websters Collegiate Dictionary, 11th ed., 2009 Diacritics in Foreign Languages As noted, there are literally dozens of diacritical marks in foreign languages. Wheeler gives these examples: Swedish and Norse words may also use the circle marking above certain vowels (à ¥), and Czechoslovakian words may use the hacek  (ˆ), a wedge-shaped symbol to indicate a ch sound as in English chill. But unless you learn- or at least develop a proficiency- in those languages, you wont know how to read the words and letters altered by diacritical marks. You should, however, learn where these marks have become common in English- and where they have been dropped, notes  Shelley Townsend-Hudson in The Christian Writers Manual of Style. It can be tricky to know when to retain the diacritical marks, she says: The language is in flux. It is becoming more common, for example, to see the acute accent and diacritics being dropped from the words  clichà ©, cafà ©, and  naà ¯ve- thus,  cliche, cafe, and  naive. But dropping diacritical marks can change the meaning of a word. Townsend-Hudson argues that in many cases you should retain these crucial marks, particularly various accents, to ensure you are referring to the correct word, such as  pà ¢tà ©Ã‚  instead of  pate: The first use means  a spread of finely chopped or pureed seasoned meat, while the second refers the crown of the head- certainly a great difference in meaning. Diacritical marks are also important when you are referring to foreign place names, such as  So Paulo, Gà ¶ttingen, and  Cà ³rdoba  and personal names such as  Salvador Dalà ­, Molià ¨re, and  Karel ÄÅ'apek, she notes. Understanding diacritical marks is the key, then, to correctly identifying and even using many of the foreign words that have migrated into the English language.