Definition: An acid is substance which in aqueous solution produces hydroxonium ion (H3O+) or hydrogen ion (H+) as the only positive ion. Also, acids can be referred to as proton donor. CLASSES OF ACIDS There are two classes of acids: (1). Organic acids occur as natural products in plants and animal material. Organic acids Source […]
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A base is a substance which will neutralize an acid to yield a salt and water only. Most oxide and hydroxide of metals are bases e.g. Na2O, K2O, MgO, NaOH, KOH e.t.c. An alkalis is a basic hydroxide which is soluble in water NaOH, KOH, Ca(OH)2. A basic oxide (or hydroxide) is a metallic oxide
OCCURRENCE OF CARBON It occurs naturally as diamond and graphite. It occurs in an impure form as coal. It occurs in the combined state as petroleum, wood and natural gases. It occurs in minerals such as limestone (CaCO3) and dolomite (MgCO3) It occur in the atmosphere (air) as CO2 It is an essential constituent of
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CARBON (iv) OXIDE The percentage composition of carbon (iv) oxide in the atmospheric air is about 0.03% by volume while in dissolved air is about 0.50% by volume. Laboratory preparation Carbon (iv) oxide is prepared in the laboratory by the action of dilute acids on a trioxocarbonate (iv) or a hydrogen trioxocarbonate (iv). Usually CaCO3,
COAL Coal is an impure form of carbon. Coal is a complex mixture of compounds composed mainly of carbon, hydrogen and oxygen with small amounts of nitrogen, sulphur and phosphorus as impurities. Carbonization of coal. Coal was formed by the gradual decomposition of plant vegetation under pressure and in the absence of air. Carbon (iv)
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H2CO3 is formed when CO2(g) is dissolved in water. H2CO3 is a weak dibasic acid. It forms two series of salts: Normal trioxocarbonate (iv) Acidic hydrogen trioxocarbonate (iv) Normal trioxocarbonate (iv) Normal trioxocarbonate (iv) may be regarded as salts derived from H2CO3 by the complete replacement of the hydrogen by a metal or cationic radical.
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HYDROCARBON AND CRUDE OIL Hydrocarbon are very simple organic compound composed mainly of hydrogen and carbon only. The sources of hydrocarbons are coal, natural gases and petroleum. Hydrocarbon can be divided into two main classes: Aliphatic hydrocarbon Aromatic hydrocarbon ALIPHATIC HYDROCARBON They are further divided into three groups: Alkanes, Alkenes and Alkynes. The Aliphatic may
CHEMICAL INDUSTRY Chemical industry is define as one that uses chemistry to make chemicals from other chemical substances (raw materials) The important raw materials used in chemical industry include (i) air (ii) CaCO3 (iii) Sea water and rock salt (iv) Sulphur (v) Metallic mineral ore (vi) Coal (vii) Natural gas and petroleum. SOURCES OF RAW
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ELEMENTS Element Definition: A chemical element is a substance that cannot be broken down by chemical means. Elements are defined by the number of protons they possess. These are the first 20 elements, listed in order: 1 – H – Hydrogen 2 – He – Helium 3 – Li – Lithium 4 – Be –
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Element Definition: A chemical element is a substance that cannot be broken down by chemical means. Elements are defined by the number of protons they possess. These are the first 20 elements, listed in order: 1 – H – Hydrogen 2 – He – Helium 3 – Li – Lithium 4 – Be – Beryllium
In chemistry, a compound is a substance that results from a combination of two or more different chemical element s, in such a way that the atom s of the different elements are held together by chemical bonds that are difficult to break. These bonds form as a result of the sharing or exchange of
The group V elements include: Nitrogen, Phosphorus, Arsenic, Antimony and Bismuth. There are more differences than similarities between the elements in this group. Nitrogen is a diatomic gas and does not exhibit allotropy. Phosphorus is a typical non-metal and exhibits allotropy. Arsenic and Antimony are metalloid; while bismuth is a metal. Nitrogen is a colourless
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Halogens (salt formers) are found in group VII of the periodic table. They are the most reactive nonmetals. They have seven valence electrons, they exist as diatomic molecules, and they are coloured and ionizes to form univalent negative ions. They form electrovalent compounds with metals. In the group are chlorine, fluorine, bromine, iodine and astatine.
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Graphite Has a high melting point, similar to that of diamond. In order to melt graphite, it isn’t enough to loosen one sheet from another. You have to break the covalent bonding throughout the whole structure. Has a soft, slippery feel, and is used in pencils and as a dry lubricant for things like locks.
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Van Der Waals Forces Intermolecular attractions are attractions between one molecule and a neighbouring molecule. The forces of attraction which hold an individual molecule together (for example, the covalent bonds) are known as intramolecular attractions. All molecules experience intermolecular attractions, although in some cases those attractions are very weak. Even in a gas like hydrogen,
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Mixtures can be separated from applying the following methods: DECANTATION Sediments can be separated from a liquid by pouring out the liquid. This process is called decantation. Experiment Put some sand in a beaker. Add about 200cm3 of water. Allow sand to settle. Pour off water carefully into another beaker. Observation Sand settles at the
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Apart from diamond and graphite, which are crystalline forms of carbon, all other forms of carbon are amorphous allotropes of carbon. Coke Coke is the amorphous allotrope of carbon, which is derived from coal. When coal undergoes destructive distillation, it yields two allotropes of carbon, namely coke and gas carbon. Destructive distillation is a chemical
In this group, we have Helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe) and Radon (Rn). The electronic configuration will show that these atoms all have a complete outer shell of electrons and are not interested in reacting with other elements. These elements are therefore chemically non-interacting and inert. They are therefore gaseous
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The halogens are all in group 7 on the right of the periodic table. This group consists of elements like Fluorine (F), Chlorine (Cl), Bromine (Br), Iodine (I), Astatine (At). The Halogens are typical non-metals and form the 7th Group in the Periodic Table ‘Halogens’ means ‘salt formers’ and the most common compound is sodium
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As well as achieving noble gas structures by transferring electrons from one atom to another as in ionic bonding, it is also possible for atoms to reach these stable structures by sharing electrons to give covalent bonds. Depending on the number of electron pairs shared between atoms which participate in bonding, covalent bonds are classified
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