FINAL ASSIGNMENT WULANTRI AKHIRIA (STOICHIOMETRY)

STOICHIOMETRY

1.    Understanding Stoichiometry

Stoichiometry comes from two Greek syllables Stoicheion meaning "element" and Metron which means "measurement". Stoichiometry is a subject in chemistry involving the linkage of reactants and products in a chemical reaction to determine the quantity of each reacting agent. Simply stoichiometry is a subject in chemistry that studies the quantity of matter in a chemical reaction

2.    The laws governing stoichiometry

The stoichiometry relies on law is like fixed comparative law, double comparative law and also the law of conservation of the masses

a.    The law of mass conservation

Using the laws of physics is like the law of conservation of mass, which holds that the mass of the reactant is equal to the mass of the product, Stoichiometry is used to gather information about the amount of various elements used in a chemical reaction

b.   Comparative law remains

This law states that the chemical compound (substance consisting of 2 (two) or more elements) always contains the same proportion of an element (compound with one atom type) with mass

c.    Law of multiple comparison

This law is one of the basic laws of stoichiometry, aside from the law of fixed comparison. Sometimes it is also called Dalton's law. It is said that, if 2 (two) elements constitute more than one compound between them, then the mass ratio of a second element which joins the fixed mass over the first element of both will have a ratio of a small sum of the whole

3.    Mass Molar (Mr)

The mass of one mole of substance is called the molar mass (relative molecular mass). The magnitude of the material molar mass is the relative atomic mass or the relative molecular mass of a substance expressed in units of grams per mole. The mass of a substance is the multiplication of its mole mass (g / mol) with the mol of the substance (n). Thus the mole relationship of a substance with its mass can be expressed as follows :

Molar mass = mass: mol

Mass = mol x Mr / Ar (molar mass)

4.    Molar Volume (Vm)

The volume of one mole of a substance in a gas form is called the molar volume, denoted by Vm. Avogadro in his experiments concluded that 1 L of oxygen gas at 0 ° C and 1 atm pressure has a mass of 1.4286 g Then, according to Avogadro's law it can be concluded:

1 mol of gas O₂ = 22.4 L

In accordance with Avogadro's law stating that at the same temperature and pressure, the same volume of gas contains the same number of molecules or the number of moles of each gas volume the same. Under the law, the volume of 1 mole of each gas in the standard state (temperature 0 ° C and pressure 1 m) is as follows:

Volume gas in standard state = 22.4 L

5.    Molarity (M)

The amount of substances present in a solution can be determined by using the concentration of the solution expressed in molarity (M). Molarity states the number of moles of substances in 1 L of solution. Mathematically stated as follows :

M = mass/mr x(1000/V)

Where:

M = molarity (unit M)

Mass = in units g

Mr. = molar mass (unit g / mol)

V = volume (mL unit)

Please watch my video :

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LESSON PLAN (RPP) CURICULUM 2013

LESSON PLAN

(RPP)

School :

Subject: Chemistry

Class / Semester: X PMS / Odd

Basic Material: Elements Periodic System

Time Allocation: 6 x 45 minutes (2 meetings)

A.   Core Competence (KI)

KI 1    : Living and practicing the religious teachings it embraces

KI 2    : Living and practicing honest, disciplined, responsible, caring (polite, cooperative, tolerant, peaceful) behavior, courteous, responsive and proactive and showing attitude as part of the solution to problems in interacting effectively with the social environment and Nature and in placing ourselves as a reflection of the nation in the association of the world

KI 3    : Understanding, applying, analyzing factual, conceptual, procedural knowledge based on curiosity about science, technology, art, culture and humanities with humanitarian, national, state, and civilization insights on the causes of phenomena and events, and applying procedural knowledge In a specific field of study according to his or her talents and interests to solve the problem

KI 4    : Processing, reasoning, and recruiting in the realm of concrete and abstract realms related to the development of self-study in schools independently, and capable of using methods according to scientific rules

B.  Basic Competencies and Indicators

1.1    Recognizing the regularity of the structure of matter particles as a manifestation of the greatness of God YME and the knowledge of the structure of matter particles as the result of human creative thinking whose truth is tentative

1.2    Shows scientific behavior (curiosity, discipline, honest, objective, open, capable of distinguishing facts and opinions, resilient, conscientious, responsible, critical, creative, innovative, democratic, communicative) in designing and experimenting and discussing the realized In everyday attitude

1.3    Analyze the relationship between electron configuration and orbital diagrams to determine the location of elements in the periodic table and the periodic properties of the elements

Indicator:

Meeting 1

·      Compare the development of the periodic system through literature study

·      Determine periods and classes of elements in the periodic table

·      Associate the electron configuration of an element with its location in the periodic system

Meeting 2

·      Classify elements into metals, non-metals, and metalloids

·      Shows the relative atomic mass of the periodic table

·      Determine the relationship between the atomic number with the nature of the elementality (atomic radius, ionization energy, electron affinity, and electronegativity)

·      Comparing the magnitudes of atomic radii, ionization, electron affinity, and electroneggency elements of one another with their atomic number or their location in the SPU

1.4    Presents the results of the analysis of electron configuration relationships and orbital diagrams to determine the location of elements in the periodic table and the periodic properties of the elements

Indicator:

Meeting 1

·      Presenting concept maps on the progress of the periodic table

·      Determine periods and classes of elements in the periodic table

·      Associate the electron configuration of an element with its location in the periodic system

Meeting 2

·      Classify elements into metals, non-metals, and metalloids

·      Shows the relative atomic mass of the periodic table

·      Analyze the tables or graphs of the periodic nature of the elements

C.  Learning Objectives

Meeting 1

1.    After doing literature study, learners are able to know the advantages and disadvantages of the development of periodic systems ranging from Dobereiner to Meyer

2.    After understanding the modern periodic system, learners are able to distinguish periods and classes

3.    Through analysis of electron-element configurations, learners are able to relate periods and classes of elements in the periodic table

Meeting 2

4.    After understanding the nature of keperiodikan, learners are able to classify the elements into metals, non metals and metalloid

5.    Learners can understand the determination of the relative atomic mass based on the abundance of elements in nature and based on the comparison to the mass of C-12 atoms

6.    Learners are able to explain the graph of the nature keperiodikan elements

D.  Learning Materials

1.    Material facts

·      The presence of Element in nature

·      Elite Periodic System

·      Elemental Properties

2.    Material concept

·      atomic number and mass number

3.    Material principles

·      Azas Aufbau

·      und rules

·      Pauli ban

4.      Procedural Material

·      Electron configuration

E.  Model and Method of Learning

a.    Approach: Scientific Approach

b.    Learning Model: Discovery Learning (Inquiry)

c.    Learning Methods: Discussion, Questioning, Assignment and percentage

F.   Media, Tools, and Learning Resources

1.    Media & Learning Resources:

·      Periodic table of elements (Dobereiner to Meyer)

2.    Tools / Materials:

·      In Focus

·      Laptop

·      Whiteboards and Markers

3.    Learning Resources:

·      Teacher handbook

·      Student handbook

G. Learning Activities:

Meeting 1

No	Activity	Description	Time Allocation
1	Introduction	·      Greetings ·      Checking for student attendance ·      Conditioning students to learn the material "Development of Elective Periodic System and Determination of Period and Element Class" ·      Frequently asked questions about element names Example: "Please name 5 elements in nature that you know?" ·      Delivering learning objectives Memberi salam	10 minutes
2	Core	·      Students are divided into 5 groups ·      Students listen to the table of the periodic system of elements based on: Dobereiner, Newlands, Mendelev and Meyer ·      In groups students are guided to: §  Observe the differences of the four periodic tables of the elements shown §  Questioning the basis of the preparation of the four periodic systems of the element §  Find and collect basic information on grouping of elements based on the development of the periodic system §  Summarizing the basis of grouping of the elements undertaken by Dobereiner, Newlands, Mendelev and Meyer ·      Students listen to the periodic system of modern elements that teachers display ·      In groups, students are guided to: §  Observing the arrangement of elements in the modern SPU §  Asking for differences in periods and classes §  Asking the condition of grouping of elements into one group and one period §  Find and collect information on the grouping requirements of elements into groups and periods based on electron configurations §  Summarizes the relationship between electron configuration with group and element period ·      Group representatives present their findings in front of the classroom and be reinforced by the teacher ·      Students do the exercises on the determination of group and element period of 5 questions	110 minutes
3	Cover	·      Teachers assign assignments to students to do at home ·      Students draw conclusions on learning outcomes at the first meeting ·      Teachers reflect on activities that have been implemented ·      Teacher submits a lesson plan plan to be delivered at the next meeting	15 minutes

Meeting 2

No	Activity	Description	Time Allocation
1	Introduction	·      Greeting ·      Checking for student attendance ·      Condition students to learn the material "Physical properties of elements and periodicity of elements" ·      Questions about metal samples and properties Example: "What does one type of metal look like?" "Mention 2 pieces of metal you know?" "What are two types of nonmetallic elements you know?" "What two non-metallic features do you know?" ·      Delivering learning objectives	15 minutes
2	Core	·      Teachers divide students into 5 groups ·      In groups, students are guided to: §  Observe the physical properties of metals and nonmetals §  Questioning criteria of elements classified into metals and non-metals §  Search and collect information on metallic and non-metallic chemical properties §  Categorize examples of non-metallic or non-metallic elements (metalloid) §  Summarizes the elements of metal, nonmetallic and metalloid elements §  Delivering the findings in front of the class, representative ·      Students listened to the symbols of several Cl isotopes displayed by teachers (Cl - 35 and Cl - 37) ·      In groups, students are guided to: §  Observing the isotope mass of Cl and the mass of Cl elements listed on the SPU §  Questioning how to determine the mass of Cl elements listed in the SPU §  Finding and collecting information on determining the relative atomic mass of elements §  Summarizes the method of determining the relative atomic mass of elements §  Delivering the findings in front of the class by group representative ·      Students are given graph of periodicity of elements ·      Students are mentored to: §  Observing the graph of the periodicity of the elements §  Questioning the nature of the characteristic properties of the elements §  Seek and collect information on the definition of the nature of the periodic properties §  Understand how to interpret the graph of the periodicity of the elements §  Summarizes the trends of characteristic properties of elements §  Convey the findings in front of the class	105 minutes
3	Cover	·      Teachers assign assignments to students ·      Students draw conclusions on learning outcomes at the first meeting ·      Teachers reflect on activities that have been implemented ·      Teacher submits a lesson plan plan to be delivered at the next meeting	15    minutes

H.  Assessment

1.    Form of Instruments and Types / Assessment Techniques:

a.    Form of Instrument in the form of Test:

No	Indicators of Competence Achievement	Assessment Technique	Instrument's Shape	Instrument
1.	Compare the development of the periodic system through literature study	Written test	Description	Attached
2.	Define periods and classes of elements in the periodic table	Written test	Description	Attached
3.	Associate the electron configuration of an element with its location in the periodic system	Written test	Description	Attached
4.	After understanding the nature of keperiodikan, learners are able to classify the elements into metals, non-metals and metaloid	Written test	Description	Attached
5	Learners can understand the determination of the relative atomic mass based on the abundance of elements in nature and based on the comparison to the mass of C-12 atoms	Tes Tertulis	Description	Attached
6	Learners are able to explain the graph of the nature of the period keperiodikan	Written test	Description	Attached

b.    Form of Non-Test Instruments:

·      Rubric and Stage Assessment Guidelines

No	Name Learners	Aspects of Attitude Assessed			NP	NM	NA	Ket
		Want to know	Cooperation	Communication
1							(NP/NM)x100
2
3

Description of attitude assessment

Want To Know (curiosity) 5 = never show attitude do not       want to know 4 = never show attitude do not   want to know 3 = several times show attitude            do not want to know 2= often show attitude do not  want to know 1 = very often show attitude do not want to know

Cooperation (team work) 5 = always cooperate 4 = often cooperate 3 = several times to cooperate 2 = never cooperate 1 = never cooperate

Communicating Good (communicative) 5 = never shows non-communicative attitude 4 = never show non-communicative attitude 3 = several times show non-communicative attitude 2 = often does not show a non-communicative attitude 1 = very often shows non-communicative attitude

No	Indicators of Competence Achievement	Instrument	Answer key	Score	Rubric
1.	Compare the development of the periodic system through literature study	Explain the different elements of element classification by Dobereiner, Newlands, Mendelev and Meyer?	·      Dobereiner classifies elements based on the increase of mass numbers, which per group consists of 3 elements and the mass of the second element is the average mass of elements 1 and 3 ·      Newlands classifies elements according to an increase in element mass number, where the 8th element is placed under the first element because it has similar properties ·      Mendelev classifies elements based on the increase in elemental mass and similarity in elemental properties. The advantage, he dared to empty a few places in the table because it believes there are other elements that at that time have not been found but the character has been predicted ·      Newlands classifies elements based on the increase of atomic number and similarity of elemental properties	20	·      Students are able to explain 4 principle of classification, score = 20 ·      Students are able to explain 3 principle of classification, score = 15 ·      Students are able to explain 2 principle of classification, score = 10 ·      Students are able to explain 1 principle of classification, score = 5 ·      Students are unable to explain any single classification principle, score = 0
2.	Associate the electron configuration of an element with its location in the periodic system	Write down the configuration of the following elements, and explain how to determine their location in the periodic system of elements: a.    16S b.    27Co	a.  16S : 2 . 8 . 6 Or 16S : 1s2 2s2 2p6 3s2 3p6 b.  27Co : 2 . 8. 15 . 2 Or 27Co : [Ar] 4s2 3d7 ·      The period of the element is determined from the number of electron occupied shells or the largest quantum number of the major ·      The class is represented by the valence electron element (the electrons residing in the outer shell). If the element configuration stops in the skin sub s or p, then the element is in the main group (A). Whereas if the element configuration stops at the d sub sub, then the element is a transitional group (B)	10	·      4 correct answers, score = 10 ·      3 correct answers, score = 7.5 ·      2 correct answers, score = 5 ·      1 correct answer, score = 2.5
3.	Define periods and classes of elements in the periodic table	Note the following X-element configuration and locate it in the periodic system of elements X : [Ar] 4s2 3d10 4p3	The element X is in period 4 and the VA class	4	·      Period and class true, score 4 ·      One wrong, score 2 ·      Both are wrong, score
4	After understanding the nature of keperiodikan, learners are able to classify the elements into metals, non-metals and metaloid	Group the following elements into metals, nonmetals and metalloids: N, K, Mg, Si, Cl, Ne, Fe, As, Cr, Kr	Metals: K, Mg, Fe, Cr Nonmetal: N, Cl, Ne, Kr Metalloid: Si, As	10	Each one answer is correct, score 1
5.	Learners can understand the determination of the relative atomic mass based on the abundance of elements in nature and based on the comparison to the mass of C-12 atoms	If known isotope Cl-35 (abundance 75%) and isotope Cl-37 (abundance 25%). Find the relative average mass of ordinary elements of Cl	Ar Cl = (isotope mass Cl-35 x abundance) + (isotope mass Cl-37 x abundance) Ar Cl = (35 x 0.75) + (37 x 0.25) Ar Cl = 35.5	6	Each step of the answer, score 2
6.	Learners are able to explain the graph of the nature of the period keperiodikan	Explain why in one class from top to bottom, the radius of the atom has a greater tendency?	The elements that are in one class from top to bottom, the number of skin increases which means the distance from the nucleus to the outermost skin becomes farther away and causes the radius of the element to increase	4	Keywords: ·      The number of skins increases (2) ·      The distance from the nucleus to the outer shell is increased (2)