IONIC COMPOUNDS In chemistry‚ an ionic compound is a chemical compound in which ions are held together in a lattice structure by ionic bonds. Usually‚ the positively charged portion consists of metal cations and the negatively charged portion is an anion or polyatomic ion. Ions in ionic compounds are held together by the electrostatic forcesbetween oppositely charged bodies. Ionic compounds have high melting and boiling points‚ and they are hard and very brittle. Ions can be single atoms‚ as the sodium and chlorine in
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Mohamed Hatab‚Ibraheem Sattour‚Rahim Fazil‚Tarik Ahroui Simple sentences‚compound sentences‚complex sentences‚compound complex sentences Simple sentence:Contains a subject a predicate‚and expresses a complete thought Ex.Some students like to study in the morning Identify the subject and predicate in these simple sentences Ex.1 1.Bill and Bob auditioned for the lead role in the play. 2.The kittens were adopted by the family. 3.Peanut butter
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The compound is the substance that can be two or more elements that can be changed. Water is a compound. It contains both Hydrogen and oxygen that can stand alone by itself. The mixture is when two different substances that are blended together. The air is a mixture of these elements carbon dioxide‚ nitrogen‚ and other stuff. Most mixtures are known to be naturally. The main difference between the compound and the mixture is how they are combined. In the pure substance‚ the only way to know if
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NON-TARIFF BARRIERS TO TRADE IN THE CORE COUNTRIES OF THE STABILITY PACT FOR SOUTH EASTERN EUROPE Study prepared by Dr. Hanspeter Tschäni Dr. Laurence Wiedmer Bureau Arthur Dunkel 56‚ rue du Stand – CH - 1204 Genève Tél : +41 22 312 48 35 – Fax : +41 22 312 48 71 E-mail : sti2@iprolink.ch ABBREVIATIONS ASYCUDA Automated System for Customs Data BiH Bosnia and Herzegovina BSEC Black Sea Economic Cooperation CAFAO Customs and Fiscal Office CAM-A/CAM-ES Customs Assistance
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COrdination compounds Question 9.1: Explain the bonding in coordination compounds in terms of Werner’s postulates. =Werner’s postulates explain the bonding in coordination compounds as follows: (i) A metal exhibits two types of valencies namely‚ primary and secondary valencies. Primary valencies are satisfied by negative ions while secondary valencies are satisfied by both negative and neutral ions. (In modern terminology‚ the primary valency corresponds to the oxidation number of the metal
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NON TARIFF BARRIERS What are non tariff barriers? Non- tariff barriers are broadly defined as any impediment to trade other than tariffs. Non tariff barriers can be classified into two groups; Direct and Indirect. (a)Direct Barriers are barriers that specifically limit import of goods or services. Eg: Embargoes and quotas EMBARGOES: Embargoes are the most restrictive of the direct non tariff barriers. They are either a complete ban on trade with a foreign nation or a ban on sales or transfer
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Organic Compounds Marilena Tagritzis 11-A Mr. Daniel Chemistry May 10‚ 2011 Organic Compounds An organic compound belongs to gaseous‚ liquid‚ or solid chemical compounds whose molecules contain carbon. Some types of carbon that contain compounds such as carbides‚ carbonates‚ and oxides of carbon and cyanides are sometimes classified as inorganic. AllotropesHYPERLINK "http://en.wikipedia.org/wiki/Allotropes_of_carbon" of carbon such as diamond and graphite may also be classified as inorganic
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1. An organic compound X with a molecular formula C2H6O undergoes oxidation with in presence of alkaline KMnO4 to form a compound Y. X on heating in presence of Conc. H2SO4 at 443K gives Z. Which on reaction with H2Oin presence of H2SO4 gives back `X` `Z` reacts with Br2 (aq) and decolorizes it. Identify X‚ Y‚ & Z and write the reactions involved. 2. An organic compound ‘A’ is widely used as a preservative in pickles and has a molecular formula C2H2O2. This compound reacts with ethanol to
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Tetrapyrrole compounds: chlorophyll and heme groups By Erwin Lim 1. Tetrapyrrole compounds A tetrapyrrole compound is a chemical group that consists of four pyrroles that are joined together by covalent bonds‚ forming a porphyrin ring. They are naturally occurring pigments‚ which are used in many biological processes (Berg‚ 2009). The basic structure of a tetrapyrrole is as seen in Figure 1‚ while the basic structure of a pyrrole is as seen in Figure 2. Figure 1.Tetrapyrrole Compound (Berg‚ 2009)
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constituent compounds discovered in past centuries - although not all aromatic compounds known today share the same distinction (many are in fact‚ odorless or even unpleasant)‚ they are the principle components in such pleasant smelling substances as cinnamon‚ licorice‚ wintergreen‚ clove & vanilla CLASSIFICATION – - also known as arenes‚ many aromatic compounds possess the benzene ring functional group: G’s FG = aromatic compound or arene benzene ring or aryl grp - other compounds which do
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