Month: November 2016

1) There will be 5 questions which I will attempt to answer.

C3H8 + O2 → CO2 + H20 → C3H8 + 5O2 > 3CO2 + 4H2O

Al2(SO3)3 + NaOH → Na2SO3 + Al(OH)3 → Al2(SO3)3 + 6NaOH = 3Na2SO3 + 2Al(OH)3

Al2O3 + Fe → Fe3O4 + Al → 4Al2O3 + 9Fe = 3Fe3O4 + 8Al

KClO3 → KCl + O2→ 2KClO₃ → 2KCl + 3O₂

NH4NO3 → N2O + H2O → NH₄NO₃ → N₂O + 2H₂O

The law of conservation of mass states that mass in an isolated system is neither created nor destroyed by chemical reactions or physical transformations. According to the law of conservation of mass, the mass of the products in a chemical reaction must equal the mass of the reactants.

The periodic table is an arrangement of the chemical elements, ordered by their atomic number (number of protons), electron configurations, and recurring chemical properties. This ordering shows periodic trends, such as elements with similar behaviour in the same column. It also shows four rectangular blocks with some approximately similar chemical properties. In general, within one row (period) the elements are metals on the left, and non-metals on the right.

Lavoisier’s Traité Élémentaire de Chimie (Elementary Treatise of Chemistry), first translated into English by the writer Robert Kerr, is considered to be the first modern textbook about chemistry. It contained a list of “simple substances” that Lavoisier believed could not be broken down further, which included oxygen, nitrogen, hydrogen, phosphorus, mercury, zinc and sulfur, which formed the basis for the modern list of elements. Lavoisier’s list also included ‘light’ and ‘caloric’, which were at the time were believed to be material substances. He has classified these substances into metals and non metals.

Dmitri Mendeleev published in 1869 the first widely recognised periodic table. He developed his table to illustrate periodic trends in the properties of the then-known elements. Mendeleev also predicted some properties of then-unknown elements that would be expected to fill gaps in this table. Most of his predictions were proved correct when the elements in question were subsequently discovered. Mendeleev’s periodic table has since been expanded and refined with the discovery or synthesis of further new elements and the development of new theoretical models to explain chemical behaviour.

Those last days. No way of wrapping it pretty or pretending otherwise Rafa was dying. Now it is my turn to take up the mantle of being man of the house. Rafa had now become a bigger priority than he already was. With ma going to church every day she leaves me to do the dirty work. Rafa was not as hard to look after, all he does is just  covers the arm chair with his body, while watching various shows on the television. All I have to do is comfort Rafa and cook food for him. Sometimes for my ma it seemed like she was the one dying. The doctors always determine that Rafa may have a few days, weeks or even months, this was a constant reminder of whats right round the corner closing in day by day.

Those last days. No way of wrapping it pretty or pretending other wise: Rafa was dead. It guess that my mom did not get any response from upstairs. The door would open with a light gentle breeze with echo of footsteps approaching. The doors within the house opened and closed. There was one room which would stay shut this was Rafa’s room. The time dinner came Ma cooked Rafa’s favourite deliquesce however Rafa was not with us. There is a thought just circling in my head that i could’ve done more for Rafa and made his life a little easier.

There was a sudden knock at the door which kept going on and on. I could hear a faint sound of a female voice. We wanted some peace, however this lady seemed adamant to come in. You would never believe who rocked up to our door. Pura. She had nerve didn’t she.

Pura walked in throwing her coat on the sofa waiting for ma. Ma gave me the look, so I knew to head straight to my room. Through the door I could hear faint shouting and distant chatter. I caught some sentences like, “you didn’t even ask about Rafa” said Ma, yet Pura kept on pleading Ma to lend her some money for her and her son, my nephew.

The time came for me to step in and boy was I angry. The silence was so loud and the tension grew and grew as did the anger inside me. I let it out there and then but no words came out. Pura’s pocket started to jingle and she placed a set of keys and ran out. She gave the car back didn’t she? Ma replied go see for yourself. I ran towards the window looking down at a part of my brother.