Inorganic Report

I. TOPIC: Sodium Metal Reactivity

II. PURPOSE: Differentiate the reactivity of sodium metal in two different medium.

III.BASIC THEORY: Alkali Metal The alkali metals are a group of chemical elements in the periodic table with very similar properties: they are all shiny, soft, silvery, highly reactive metals at standard temperature and pressure and readily lose their outermost electron to form cations with charge +1. They can all be cut easily with a knife due to their softness, exposing a shiny surface that tarnishes rapidly in air due to oxidation. In the modern IUPAC nomenclature, the alkali metals comprise the group 1 elements,¬¬ excluding hydrogen (H), which is nominally a group 1 element¬¬ but not normally considered to be an alkali metal. All the alkali metals react with water, with the heavier alkali metals reacting more vigorously than the lighter ones. The alkali metals are lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr). All alkali metals have their outermost electron in an s-orbital. The alkali metals provide the best example of group trends in properties in the periodic table, with elements exhibiting well-characterized homologous behaviour. All the discovered alkali metals occur in nature. Experiments have been conducted to attempt the synthesis of ununennium (Uue), which is likely to be the next member of the group, but they have all met with failure. However, ununennium may not be an alkali metal due to relativistic effects, which are predicted to have a large influence on the chemical properties of superheavy elements. The atoms do not have a strong attraction for the single valence electron, and so it is easily lost (small first ionization energy) to from a +1 ion. Because they readily donate electrons in this way, all the alkali metals are strong reducing agents. They are quite reactive, even reducing water. Weak attraction for the valence electron also results in weak metallic bonding, because it is attraction among nuclei and numerous valence electrons that holds metal atoms together. Weak metallic bonding results in low melting points, especially for the larger atoms toward the bottom of the group. Cs, for example, melts just above roomtemperature. Weak metallic bonding also accounts for the fact that all these metals are rather soft.

 IV. TOOLS AND MATERIALS
1. Beaker Glass 200 mL
2. Cutter
3. Measurement Glass 50 mL
4. Tissue sufficient
5. Pipettes
6. Thinner 25 mL
7. Sodium Metal Little beat
8. Aquadest 25 mL
9. PP indicator ±2 mL

V. PROCEDURES:
1.added 50 mL of distilled water into the beaker.
2.Added 3 drops of indicator glass PP and PP indicator shaken to spread throughout the water layer. 3.added 25 mL of paint or paint thinner to two-phase separation is clearly visible.
4.Sodium metal is cut with a knife or a cutter and then cleaned with a paper towel to remove as much as possible paraffin, and then immediately put into a beaker.
5.Observed what changes or reactions that occur such as discoloration, presence of gas or changing the temperature (can be estimated by touch the outside of the beaker) and recorded in observation sheet. 6.Allow the reaction to completion (until all the sodium metal depleted), and throw straight into the hole sink while the water flowed from the faucets.

 VII. DISCUSSION

Most of the elements that exist in nature are metals. Of the 92 kinds of natural elements, which include 70 types of metals. Metals have many different physical properties of the physical properties of other solids. It can be seen from the reflected power, conductivity, and mechanical properties owned by the metal. Some metals have the specific color of the flame and to reinforce the color produced, commonly used indicators. Phenolphthalein is another commonly used indicator, phenolphthalein, and this is another weak acid. IA group also called alkali metals. Alkali metals and minerals are abundant in sea water. Especially Na (sodium), metals in the earth's crust, including the fourth largest after Al, Fe, and Ca. Although the presence of sodium and potassium ions have been recognized for a long time, a number of attempts to isolate the metal from the salt water solution failed because of high reactivity in water. In this experiment, we conducted experiments to observe the reactivity of sodium in two different medium and used to test whether the PP to form an alkaline solution as an indicator of changing pp warn at a pH of about 8 (alkaline pH). When the paint thinner and water are mixed in a container formed two-phase solution, this occurs because as we all know that the most common solvent is water. Other common solvents dissolve substances That the which are insoluble (or nearly insoluble) in water are acetone, alcohol, formic acid, acetic acid, formamide. BTX, carbon disulfide, diemthyl sulfoxide, carbon tetrachloride, chloroform, ether, tetrahydrofuran, furfural, hexane and turpentine. They may be classified as polar and non-polar. Polar solvents, like water, have molecules Whose electric charges are unequally distributed, leaving one end of each molecule more positive than the other. Usually polar solvent has OH bond of the which water (HOH), (CH3OH) and acetic acid (CH3COOH) are examples. Propanol, butanol, formic acid, formamide are polar solvents. Dipolar solvents the which contain a CO double bond without OH bond are acetone [(CH3) 2C = O], ethyl acetate (CH3COOCH2CH3), methyl ethyl ketone, acetonitrile, N, N-dimethylformamide and diemthyl sulfoxide. Nonpolar solvents, like carbon tetrachloride (CCl4), benzene (C6H6), and diethyl ether (CH3CH2OCH2CH3), Whose molecules have electric charges are equally distributed and are not miscible with water. Hexane, tetrahydrofuran and methylene chloride are non-polar solvents. Polar solvents are hydrophilic but non-polar solvents are lipophilic. Polar reactants will dissolve in polar solvents. Non-polar solvents dissolve non-polar compounds best. Oil and water do not mix but separate into two layers. There are three measures of the polarity as "dipole moment", "dielectric constant" and "miscibility with water". Though low dipole moments and small dielectric constants indicate non-polar solvents, sharp boundaries between polar and non-polar solvents are not available. The polarity reflects the balance between a polar component (OH) and a non-polar hydrocarbon component, existing in the same molecule. If hydrocarbon character increases relatively, the polarity decreases. On an operational basis, solvents are miscible with water that are polar. So, when a thinner dissolved in water, formed into two layers is due to differences in polar and non polar in which, only a substance will dissolve in a suitable solvent. In other words, which are polar substances will dissolve in polar solvent and a non-polar substances will be soluble in non polar solvents. (Like dissolved like principle). When the sodium added to a solution that already contains thinner, water, and PP, the sodium will float in water (upper layer) as a light metallic sodium will make sodium floats. Because the sodium metal is a metal that is very reactive to water, even water vapor contained in the air though. Therefore, in penyimpannnya, sodium stored in paraffin, to prevent direct contact between the metal with water vapor in the air. This is due to moisture can not penetrate the wax due to differences in polar (water is polar, while the paraffin is a non-polar compound). So, when you want to use paraffin at about sodium should be cleaned in advance in order to react with water. Sodium floats on the surface, but the heat released by reaction is sufficient to melt the sodium (sodium has a lower melting point than lithium and the reaction occurs more rapidly generates heat) and sodium melt almost at once to form a small silver dots scattered over the surface. There are white marks of sodium hydroxide in water is visible beneath the dots of sodium, but the scars were immediately dissolved to give a solution of sodium hydroxide is colorless. Sodium moving on the surface because of pressure from all directions by the hydrogen released during the reaction. If the sodium trapped at the edge of the container, then the hydrogen can be burned and produce a flame orange. This color is caused by contamination of the blue flame of hydrogen by sodium compounds. At the time of Na metal was added to the mixture solution in which there is (water, thinner and indicator pp) temperature changes are marked with the wall surface of the glass becomes warmer and when sodium reacts temperature drops back out (to cooler). This suggests that the reaction between sodium and water is an exothermic reaction because it can generate heat. In this experiment, very little sodium is used to avoid an explosion due to the extremely high reactivity of sodium can cause a huge explosion. Moreover, by its nature that the sodium (Na) is highly reactive to oxygen (O2) and water (H2O). Na metal reactivity caused by outer shell electrons are weakly bound nuclei, so easily dislodged. Besides Na metal is the redactor and can reduce water to form a base and hydrogen release. Based on the experiments we did, it also arises from the reaction of the bubble, the gas or smoke is white, produce odor, color fading solution, is depleted of sodium metal in solution, the faded color of the solution. This is due to Na metal which, when reacted with water will result in an alkaline solution which is characterized by a color change indicator PP lilac color, which indicates that the solution is alkaline. PP is an indicator of organic compounds that can release H+ in water by the equilibrium reaction: HIn + H2O ↔ H3O + + In- Where in this equilibrium, HIn molecule is a molecule that is colorless, while the In-gives the red color in the solution. Therefore, if the equilibrium shifts toward the formation of In-, then the solution will be colored red. This equilibrium shift may occur with the addition of a solution containing OH-ions: HIn + OH → In-+ H2O The addition of phenolphthalein indicator in the reaction products can provide an explanation of the reactivity of metal, where the stronger the red color is formed after the addition of the indicator, means that more OH ions which have been formed, which indicates that the more reactive metal. Simply put, the reaction between sodium and hydrogen can be written as: Na(s) + H2O(l) → NaOH(aq) + H2 (g) The presence of bubbles that appear in this reaction indicates that the formation of H2 gas. So, from the experiment can be proved that, in accordance with its sodium (Na) is highly reactive to oxygen (O2) and water (H2O). Na metal reactivity caused by outer shell electrons are weakly bound nuclei, so easily dislodged. Besides Na metal is the reductant and can reduce water to form a base and hydrogen release. Because of the reactivity of sodium metal as mentioned above we are advised not to touch students sodium metal with bare hands, because these metals can react with water on hand and can cause fire or explosion.