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By Doreen Eweama Born into an affluent family, I did not lack anything I needed or wanted. I am Susan Ken, a tall, slender and fair-skinned girl. I have three siblings. I am a brilliant and beautiful twenty-one-year old, the dream child of every parent. Unlike my siblings, I never caused trouble in within and without the neighbourhood, which made my parents proud of me. I attended one of the most prestigious secondary schools in the country, and as a final year student, I was under a lot of pressure from my parents, teachers and relations. Being serious-minded, I hardly engaged in any activity that would not add any positive value to my life. After months of studying, the time we were all preparing for eventually came - the Senior School Certificate Examination (SSCE). Many of my mates were scared, but I drew confidence and inspiration from my mother's saying, "Prior Planning Prevents Poor Performance", what I also call, 'The 5P's Escape Route From Failure'....

By Esther Olorunshola Growing up was a miserable experience for me. My childhood days were nothing good to write about and most times, I wished I was never part of history. Living without a father nor a mother made things worse as I had to fend for myself without the help of any relatives. Ours was one small and happy family until July 19, 1995 when everything took a U-turn. I was alone with my parents in the car. We were on our way to the beach to mark my 10th birthday. I sat at the owner's corner while my mother sat close to my father. Out of excitement, probably because it was long we went to the beach, I mistakenly covered my dad's face with a cloth, and before he could uncover his face, he lost control of the steering, swerved to the bush and the rest is history. My name is Goodwill and I am a paraplegic. At age 7, I was struck by mild poliomyelitis, the condition, however, was worsened by the accident that claimed my parents' lives. My uncles saw me as a huge liabi...

Water of crystallization (WC) is the number of molecules of water present in one mole of a hydrated salt. Example, in iron (II) tetraoxosulphate (VI)-heptahydrate [FeSO4.7H2O], there are seven molecules of water attached to a molecule of FeSO4, that is its water of crystallization. Some other examples of salts with water of crystallization include: MgSO4.7H2O - Magnesium tetraoxosulphate(VI)-heptahydrate, (Epsom Salt) CaSO4.2H2O - Calcium tetraoxosulphate(VI)-dihydrate (Gypsum) Na2CO3.10H2O - Sodium trioxocarbonate(IV)-decahydrate (Washing Soda) CuSO4.5H2O - Copper (II) tetraoxosulphate(VI)-pentahydrate (Blue Vitriol) ZnSO4.7H2O - Zinc tetraoxosulphate(VI)-heptahydrate (White Vitriol) Cu(NO3)2.3H2O - Copper (II) trioxonitrate(V)-trihydrate From the above examples, it can be observed that each salt has a definite number of molecules of water of crystallization attached to it. Therefore, it can also be defined as the definite amount of water some substances chemically combine wi...

John Dalton in one of his postulations of Atomic Theory stated that atoms of the same element are alike and different from atoms of other elements . This was, however, faulted with the discovery of nucleon mass (mass number) and neutrons by Rutherford and Chadwick respectively. Studies showed that there are atoms of the same element that have the same atomic number, but different mass numbers as a result of the difference in their number of neutrons. These atoms are called isotopes and the phenomenon is known as isotopy. Examples of elements that exhibit isotopy include chlorine (Cl-35 and Cl-37), carbon (C-12, C-13 and C-14), oxygen (O-16, O-17 and O-18) etc. In reality, all elements exhibit isotopy because this explains why the relative atomic masses of elements are not whole numbers . Relative Abundance of Isotopes In a particular element, say chlorine, the two isotopes - Cl-35 (chlorine-35) and Cl-37 (chlorine-37) are present in different quantities of...

Definition of Terms Solute This is a substance that dissolves in a solvent to form a solution. It can be solid, liquid or gas. Examples include common salt, sugar, copper (II) tetraoxosulphate (VI) etc. Solvent This is a substance that dissolves a solute to form a solution. It can be liquid or gas. Examples are water, ethanol, benzene etc. Solution This is a mixture of solute and solvent, i.e,          Solute + Solvent = Solution It can be homogeneous with a uniform composition, e.g, an unsaturated solution of a sodium chloride, or heterogeneous with non-uniform composition like an unsaturated solution of the same salt. Saturated Solution A saturated solution is one that holds as much solute as it can dissolve in the presence of undissolved solute particles at a given temperature. In a saturated solution, the dissolved and undissolved solutes are in equilibrium at a given temperature. Unsaturated Solution An unsaturated solution is one...

The Gay-Lussac's Law of Combining Volumes states that when gases react, they do so in volumes, which are in simple ratio to one another and to the volume of the product, if any; provided temperature and pressure remain constant. It applies to only gases, which means that solid and liquid reactants and products are always ignored when applying this law. For instance, hydrogen burns in oxygen at 100°C to form steam according to the equation:        2H2(g) + O2(g) ---> 2H2O(g)          2mol      1mol           2mol          2vol        1vol            2vol          2cm^3    1cm^3        2cm^3 From the above, it implie...