Using English To Report

Class and element identification

CHAPTER I

PRELIMINARY

1.1 BACKGROUND

The element identity is the determination or determination of the identity of an element. Which is the identity of the elements are the special features or circumstances of the element. The identification of this element is a step in the chemical analysis. Chemical analysis is an investigation that aims to find the compounds or compound mixtures in a sample. In addition to the identification of steps in the chemical analysis of the constituent estimates of the components of a compound. The identification step is known as qualitative analysis as the step of estimation is quantitative analysis. Qualitative analysis is concerned with the identification of chemical substances, recognizing which elements or compounds are present in a sample. Quantitative analysis deals with the determination of several many of the particular substances contained in a sample.

Qualitative analysis there are two important aspects, namely, identification and separation, this aspect is based on solubility, acidity, alkalinity, the formation of complex compounds, oxidation-reduction, the nature of evaporation and extraction. Qualitative analysis is usually used in the identification of cations and anions by performing a specific ui. Specific tests are carried out with the addition of certain Reagan (reagents) which will provide a solution or color deposit which is characteristic (typical) for certain ions.

Therefore, this pratikum is done with group titles and element identification with the aim of studying the acidity of the properties of the elements in the periodic table, observing the flame test and reaction of some alkaline and alkaline earth elements, recognizing the reaction of chlorine and halide water and analyzing the anu solution containing elements Alkali or alkaline earth and halides. The experiment will be carried out by analyzing some sample solution with some tests to be able to classify and identify certain elements.

1.2 PURPOSE OF PRATICUM

1. Can know to study the similarity of the properties of the elements in the periodic table

2. Can know observe flame test and reaction of some alkaline and alkaline earth elements

3. Can know to recognize chlorine and halide reactions

4. Can know to analyze an aqueous solution containing alkaline or alkaline earth elements and halides

CHAPTER II

THEORETICAL BASIS

According to (sunarya, 2010: 334-335) To date, 115 elements have been found with their distinctive properties for each element. The similar properties of the various elements are assembled in a group, a different set of traits separated and grouped into other sets. The first grouping of elements is based on the properties of metals, not metals and semilogam, then the grouping is based on the atomic period, which at that time was known. Knowing that the atomic number is a characteristic element, the organizing of elements is arranged in order of atomic numbers. The first person to construct the periodic table of elements is Johan w. Dobereiner. The arrangement is based on atomic masses based on Dalton atomic theory. The elements located at the curve points have almost identical properties. Mendelev devised a periodic table of elements based on chemical and physical properties and sorted by atomic masses alike. Advantages mendelev is the ability to predict the properties of elements that have not been found at that time.

According to (sunarya, 2010: 334-335) states that when elements are ordered according to atomic number increases, elements of a similar nature differ in the same class. Elements in the same class have the same number of electrons in the outer shell, such as Li and Na; Or Be and Mg, and so on. The outer shell contains valence electrons called valence skin. Since the elements in one group have similar properties and valence electrons are the same, the properties of the elements are closely related to the atomic valence electrons, it can be stated that the periodic table is an arrangement that places elements with the same number of valence electrons in the same class . In the periodic table, the rate from the left of the right is called period; And the rate from the top down is called the class.

According to the IUPAC rules, there are 18 groups, as according to the American rule consisting of 2 groups, namely Group A (main group: IA-VIIIA) and group B (transition group: IB-VIIIB). Some Class A have special names such as: IA (Alkali), IIA (Alkali soil), VIIA (Halogen), and VIIIA (noble gases). Period in the system periodic consists of 7 periods. The position of the elements (classes and periods) in the system periodic can be determined based on the electron configuration. The class number denotes the number of valence electrons, the period number represents the number of skins.

CHAPTER III PRATICUM

3.1 METHODS

TOOLS AND MATERIALS Tool: Material: • Test tube - 0.5 M BaCl2 solution • Test tube rack - CaCl2 0.5 M solution • Nichrome wire - 0.5 M LiCl solution • Bunsen - a 0.5 M KCl solution • Pipette drops - 0.5 M NaCl solution • Wood clip - SrCl solution 0.5 M • Matches - a concentrated HCl solution of 12 M • Napkins - 0.5M ammonium carbonate solution • Roll wipes - ammonium sulfate solution - 0.5 M NaBr solution  - tetrachloride solution  - dilute nitric acid 6 M  - distilled water - 0.5 M NaCl solution - water chlorine

3.2 WORK PROCEDURES

A.Flame Test For Alkaline and Alkaline Soil Elements • Inserted each into the test tube • Take a nikrom wire • Heated on the blue part of bunsen flame • Heat it until it is colorless • Dipped wire into tube containing barium solution • Heated wire tip on a strontium flame • Cleaned wire • Perforated flame test for solutions containing calcium, lithium, sodium, strontium

A. Flame Test Alkali and Alkali Elements

NO Substance reagents Description

1 CaCl2 Alkaline Red

2 BaCl2 Yellow green Alkali soil

3 SrCl2 - -

4 KCl Purple Alkali

5 NaCl Yellow Alkali

6 LiCl - -

B. Analysis of an aqueous solution

4.2 DISCUSSION

In this experiment we discussed the classification and identification of the elements in which there are four experimental steps namely the alkali and alkaline earth flame tests, alkali and alkaline earth elements reactions. Halide reactions, and analysis of such solutions (x and y).

A. Flame Test Alkali and Alkali Elements

The number of elements is numerous and the number is experienced. The elements are arranged in the periodic table of elements grouped in columns called groups and in rows called periods. The groupings are structured on the basis of the resemblance of elemental properties. Each element has its own characteristics, and has a flame test to distinguish one element from another. According to IUPAC rules there are 18 groups and 7 periods. In this pratikum will be discussed about experiments on the alkaline and alkaline earth classes. Alkali is a metal of the main group whose elements are in class IA. There are 6 elements found in the alkaline group namely lithium, sodium, potassium, rubidium, cesium and franium. Alkali is not free in the environment but is present in the compound form because the alkaline element is highly reactive. The alkali elements are referred to as such because they can form strong bases. Alkaline soil is a class IIA element found in the form of an insoluble compound in the soil. The alkaline earth elements have two more electrons than the noble gas element. The meaning of element identification is the determination or determination of the identification of an element in which the identity of the element is a characteristic or special circumstance of the element. This experiment aims to observe the properties of the elements, identifying the elements through the flame test. The flame test can be observed from the solution using the nichron wire.

In theory, the color of the alkali metal flame: LiCl: red NaCl: yellow KCl: purple RbCl: red CsCl: blue Fransium: - Alkaline earth metal flame color: Be: white Mg: white Ca: red orange Sr: red Ba: green Based on the theory and experimental results that have been done, the color we get the same color in theory.

CHAPTER V

COVER

Based on the results of experiments we have done, it can be concluded that:

1. Each element has distinctive properties, in one group there is a similarity in the nature of its elements, if the elements in the class IIA reacted will produce all sediment and class IA does not happen sediment. Elements of class IA easily dissolve and the lower the nature of the stronger. Group IIA has a difficulty to dissolve and is a weak base.

2. Group IA has a distinctive flame, namely:

Li: red

Na: yellow

K: purple

Rb: red brick

Cs: blue

Group IIA has a distinctive flame, namely:

Be: white

Mg: white

Ca: red orange

Sr: red

Ba: green