Elements In Chemistry

There have been many attempts to organize the elements in a systematic manner such as Dobereiner’s triads, Newlands’ law of octaves, but periodic table of elements is considered to be the most useful and convenient resource in the field of chemistry today for it positions the elements in an instructive arrangement [7].

The periodic table of elements is based mainly on the combined efforts of Russian chemist, Dmitri Mendeleev and a German physicist, Julius Meyer, arranging the elements in order of increasing atomic weights, being observed as well after it was being done that similar physical and chemical properties recurred periodically [7]. The periodic table is composed of 118 entries of elements, arranged in rows being called periods. The

The students started to obtain aluminum, magnesium, silicon, phosphorus, and sulfur samples in a powder form; sodium metal that was stored with kerosene, since sodium metal is highly reactive with moisture from the air that causes to burn violently, kerosene has a very low vapor pressure at ambient temperature that makes it selected for storage among other petrochemicals to prevent the element to burn; and lastly, chlorine gas that was dissolved in water so that it may be visible to the eye of the observant. After which, all samples were placed in their respective labeled test tubes and were rested in a test tube rack for observation of their physical properties like its state, its color, and whether it is lustrous or not. The students gathered the data and accomplished the first part of the

The students then found out that after adding a drop or two of a litmus indicator, a basic solution, as seen with the potassium (KOH) solution, gave off a blue-ish color. While an acidic solution, as seen with the hydrochloric acid (HCl), showed off a pink-ish color.

The resulting products of having water solutions [4], upon dissociation to water that served as the solvent on the different oxides being the solute, showed that an acidic one Increases H+ ion concentration in a solution, as a basic Increases OH- ion concentration in a solution [1]. Acids are further described to have a sour taste, neutralizes bases, corrosive, and reacts with active metals to produce hydrogen gas. Meanwhile, bases are said to have a bitter, biting taste, slippery, and neutralizes acids [7].

However, with the results attained by the students, aluminum and silicon had a little difference in terms of the results in their colors. It is because these two did not have a reaction with water. In which the students learned that aluminum is an amphoteric oxide wherein it reacts with both bases and acids, while silicon is considered an acidic oxide but is insoluble with water. After which, students then learned from the results another trend that oxides of its elements in the third period are basic to amphoteric to acidic as it goes across from left to