FL Clear F C F LL F Available Electrons: 32 Create the Lewis structure of CF4. NOTE: do only the step asked for in each part and then click Check-don't work ahead to solve the final structure. Step 1. Count valence electrons in the molecule or ion. Do this by adding the periodic group numbers for each atom in the structure and adjusting for charge. Enter and Check. Step 2. Connect each pair of bonded atoms with a single bond by dragging bonds onto the molecule. Each bond decreases the number of available electrons by 2. Check.

structures of atoms.jpg Close Lewis Structures Name: Lews structures, or dot Cagrams, are a simplined way to show how the valence electrons are arrangedn the outer shell. This is where the chemical reactions tahe place. Atons will either share or give away these electrons to form bonds. • Using your periodic table, determine the number Draw a dot to roprosont each valonco oloctron around tho alomont symbol. • Follow the pattorm below starting with position number 1. valence electrons for each element 1, 5 4 Examples: H. 8 Ва In Не 3, 7 Li Ве Ne Na Mg Al Si CI Ar Period 5, Esler, Chemistry K Са P.

vo/index.html?deploymentld%35575082893 288909969212&elSBN=9781305657571&snapshotld%3D2199898&id%3D1... NDTAP Q Search this cour Use the References to access important values if needed for this question. Draw (on paper) a Lewis structure for SF2 and answer the following questions based on your drawing. Do not draw double bonds unless they are needed for the central atom to obey the octet rule. 1. For the central sulfur atom: the number of lone pairs the number of single bonds the number of double bonds = Numeric input field 2. The central sulfur atom A. obeys the octet rule. B. has an incomplete octet. C. has an expanded octet. Submit Answer 5 question attempts remaining

Show how these elements combine into octet-rule ionic compounds, as in the first example. First, draw atomic Lewis structures for the atoms and their O.R. ions.  Show their charges, and use them to find the unit formula, and the name.  Then draw atomic Lewis structures for all atoms in the formula unit together, show with arrows how all e¯s are transferred to make the ions, and draw the Lewis structure of the ionic compound. Atoms O.R. ions Unit formula Lewis Structure Name Transfer e¯s with arrows Mg    +   Br       Magnesium bromide   Li    +     C       Lithium carbide   Ge    +    S

I. Directions: Draw the lewis structures of the neutral w atom and the ion of each element. Determine the number of electrons gained or lost in forming an ion. Lewis Structure Number of Electrons Element Neutral lon Gained Lost Atom 1. Potassium 2. Carbon ||

Choose the INCORRECT statement. Select one: O a. Formal charges are apparent charges associated with atoms in a Lewis structure. Ob. In a Lewis structure, the number of valence electrons shown is one more for each negative charge. O. The central atom is typically the atom with the highest electronegativity. Od. Resonance is when more than one equally plausible structure can be written In a molecule, hydrogen and halogen atoms are always at terminal positions e.

1. Consider the structure shown below and then answer the following questions. a. Complete the structure by adding the missing formal charges. All atoms and lone pairs are explicitly shown. (Hint: Consider the number of bonds neutral atoms have.) :Ö: H ‚H H H b. Draw two more resonance structures of the molecule from part a by adding the missing î bonds, lone pairs, and formal charges. All atoms in both structures should possess an octet. (All atoms and o bonds are drawn for you; remember, only lone pairs and bonds move in resonance structures.) Additional guidelines are given for each structure. All atoms in this structure will be neutral (no formal charges). One oxygen atom has a +1 formal charge and one oxygen atom has a -1 formal charge. H H H H H H H H H

Show how these elements combine into octet-rule ionic compounds, as in the first example. First, draw atomic Lewis structures for the atoms and their O.R. ions. Show their charges, and use them to find the unit formula, and the name. Then draw atomic Lewis structures for all atoms in the formula unit together, show with arrows how all e s are transferred to make the ions, and draw the Lewis structure of the ionic compound. Unit formula Atoms O.R. ions Name Transfer e s with arrows Lewis Structure LizN le 1e 30 Lithium Li. + •N• Li. •N• Li. Li 30 Li Li Li :N: nitride )le Li. Pb and K and H

Show how these elements combine into octet-rule ionic compounds, as in the first example. First, draw atomic Lewis structures for the atoms and their O.R. ions. Show their charges, and use them to find the unit formula, and the name. Then draw atomic Lewis structures for all atoms in the formula unit together, show with arrows how all e s are transferred to make the ions, and draw the Lewis structure of the ionic compound. Unit formula Atoms O.R. ions Name Transfer e s with arrows Lewis Structure LizN le 1е 30 Li. + •N. Lithium nitride Li. N: Li. 30 Li :N Li Li Li :N: Li. Jle Mg + Br Li + C Ge +

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