top-rated free essay

Lab Assignment lewis dot

By MellKenney Apr 20, 2015 1005 Words
 Melissa Kenney Dr. Braun/Lab K Lewis Symbols & Structures

Purpose
The purpose of this lab experiment is to practice writing Lewis symbols for elements and monatomic ions while writing Lewis structure for molecules and polyatomic ions. I will also be writing chemical equations using Lewis structures for different reactions involving either ionic compounds or covalent compounds. Lastly, I will I will predict the empirical formulas of ionic and covalent compounds based on the Lewis symbols for their ions and atoms, while also writing Lewis structures for the compound as well. Background

Chemists utilize models in order to better understand the nature of any matter they are studying. These physicals model often allow chemists to better understand the shape and relative size of atoms, molecules, and ions that make up the substance and the spatial relationships amongst all of these components. In these models every atomic nucleus is surrounded by at least one electron, of which only the valence electrons are chemically active. To illustrate this chemists use a model known as the Lewis electron-dot symbol which illustrates both the chemical symbol and the electron dots. The bonds that hold the atoms of a substance together are illustrated through the use of a Lewis structure, which shows the different atoms and their numbers in the species as well as the distribution of all valence electrons. The portion of the Lewis symbol that represents the nucleus and inner, non-valence, electrons of one atom is called the atomic core. In this model the valence electrons are represented by using dots around this atomic core symbol. When putting together this Lewis symbol the model is constructed by arbitrarily placing the electron dots one at a time on each of the four sides of the atomic core until all of the valance electrons are represented. In chemical reactions, electrons are shared and transferred between atoms which produces ionic or covalent compounds. A compound made up of a combination of positive and negative compounds is known as an ionic compound. Subsequently, the attraction that holds these oppositely charged ions together is known as an ionic bond. In the species where there is bonding between atoms in a molecule or polyatomic ion, pairs of electrons are shared between atoms which form a covalent bond. These atoms that are joined by covalent bonds then form covalent compounds. When the outer electron levels of atoms reach their maximum of eight electrons they are referred to as an octet, thus we say that this configuration is in accordance with the octet rule. When a hydrogen atom has only two electrons, this configuration is then in accordance with the duet rule. We can also use Lewis structures to predict the empirical formula of a substance from the reaction of two elements. An example would be the reaction between silicon and hydrogen, where each silicon has an electron octet and each hydrogen has an electron duet. With that ratio being four hydrogen atoms bonding to each silicon atom, the empirical formula can be computed to be SiH4. In this experiment, I will write chemical equations using Lewis symbols and Lewis structures to represent reactants and products. Based on the Lewis symbols of selected elements, I will determine the possible empirical formula and Lewis structure for these products.

Procedure
I will begin this lab by filling in the Lewis symbols for the third period elements that are listed. I will then write the Lewis symbol for the listed ions and construct the Lewis structure model for the ionic compound potassium chloride using the following steps; identify the number of valence electrons, identify the atomic cores for potassium and chloride ions, writing the Lewis symbol for each one, Writing the Lewis structure, and identifying the difference in structure between the two. I will then construct the Lewis structure model for the covalent compound hydrogen sulfide using the same before mentioned steps. Next I will construct the Lewis structure model for the covalent compound sulfur difluoride by identifying the number of valence electrons, arranging the atomic cores, rewriting the atomic cores with electron pairs, and writing the Lewis structure while distributing the remaining valence electrons so that all three atoms are in accordance with the octet rule. Once completed I will then construct the Lewis structure model for the covalent compound methylene chloride using the same steps previously listed. I will then construct the Lewis structure model for the covalent compound carbon tetrachloride by identifying the total number of valence electrons, writing the atomic core for the element with the central atom surrounded by the remaining atomic cores, writing the Lewis structure after distributing the remaining valence electrons so that each chlorine atom has an electron octet. Once completed I will then utilize these same steps to construct the Lewis structure for the covalent compound phosgene while considering the possibility of a multiple bond between two of the atoms if I have trouble placing all of the valance electrons. I will then construct the Lewis structure for the covalent compound silicon dioxide using this same process, while also writing the Lewis structure for the hydrosulfide ion and covalent molecule nitrogen in individual boxes while identifying the number of valence electron for each structure. Once completed, I will then fill in the table given by writing the empirical formula and the Lewis structure for potassium iodine, calcium fluorine, and sulfur chlorine. I will do this by assuming that the first two pairs of elements react to form iconic compounds while the third forms a covalent compound. I will also refer to the periodic table to determine the number of valence electrons for each of the elements given. Once this table is complete I will then write both an equation using Lewis structures and a balanced chemical equation for the following reactions; silicon atoms and chlorine molecules, lithium atoms and bromine molecules, and ethylene molecules and chloride molecules. Once completed I will then predict the empirical formula and Lewis structure of both the hydride of selenium and hydride of tin.

Cite This Document

Related Documents

  • lewis dots structure

    ...Lewis Structures and the Shapes of Molecules Pre-Lab Assignments: To be assigned by your lab instructor. Student Learning Outcomes: Learn how to draw Lewis structures. Learn how to draw Lewis structures for atoms which violate the octet rule. Learn how to use Lewis structures and VSEPR and to predict the shapes of molecules. ...

    Read More
  • Writing Lewis Electron Dot Structure

    ...Writing Lewis Dot Formula November 8, 2013 I. Learning Objectives At the end of the sessions, the students of III- 15, and III – 10 must be able to: 1. Students will be able to interpret and draw Lewis dot diagrams for individual atoms and both covalent and ionic compounds. II. Subject Matter A. Topic: Chemical Bonding B. References ...

    Read More
  • Chemistry Bonding Notes and Lewis Dot Structures

    ...Shortest v. Double Bond w. Single Bond xxxviii. Weakest xxxix. Longest xl. Lowest Bond Order IX. Resonance x. More than one Lewis Dot Structure can be drawn for the same arrangement (skeleton) of atoms. Only the bonds differ! y. True structure is a ‘hybrid’ or ‘blend’ of po...

    Read More
  • Assignments

    ...Science Assignment | March 22 2013 | Jessica Finney | Ms Croaker – Sc743A | Science Part A Assignment Choose one scientist involved in formulating the modern periodic table and describe why their work made a significant contribution to the development of the periodic table. Dmitri Mendeleev’s contribution to the modern day peri...

    Read More
  • Lab Assignment

    ...Instructions Assignment 4 A. Part A – Location of the Heart and Heart Valves Exercise 27 Activity 1 Surface Features of the Heart and Location (7 points total) Lab Activity 2 Insert a photo of the following marked on your shirt (use tape and labels or plastic instead of marking on your shirt). 1. The 4 corners of the heart (1 ...

    Read More
  • Lab Assignment

    ...Observing Bacteria and Blood Abstract The purpose of this exercise is to gain knowledge on basic skills to correctly operate a microscope by viewing blood and bacteria through different magnifications Hypothesis This exercise will help me gain knowledge and the correct way to use a microscope. This will also help me for future observa...

    Read More
  • sugar lab

    ...Burning Sugars lab 3rd Hr Andrew Ativie 5/11/14 For the “Burning Sugar Lab” I was asked to make a prediction on what i might have thought the different types of products that would be produced from this experiment. I Stated that Water, Oxygen, Hydrogen, and Carbon would be produced. Because those were the elements that were liste...

    Read More
  • assignment

    ...phones to school. It is very reasonable because bringing phone toschool potentially disrupts the learning process. Moststudents use cell phones irresponsibly. They use cell phones to talk to their friend during class time. They also use the calculator and camera features in the class as well. Those potentially lead less concentration in the ti...

    Read More

Discover the Best Free Essays on StudyMode

Conquer writer's block once and for all.

High Quality Essays

Our library contains thousands of carefully selected free research papers and essays.

Popular Topics

No matter the topic you're researching, chances are we have it covered.