Using each of the following electron arrangements, give the formulas for the cation and anion that form, the formula for the compound they form, and its name.

State the number of valence electrons, bonding pairs, and lone pairs in each of the following Lewis structures:

c.

Match each of the Lewis structures (a to c) with the correct diagram (1 to 3) of its shape, and name the shape; indicate if each molecule is polar or nonpolar. Assume X and Y are nonmetals and all bonds are polar covalent.

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c.

Match each of the formulas (a to c) with the correct diagram (1 to 3) of its shape, and name the shape; indicate if each molecule is polar or nonpolar.

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a. PBr₃

Consider the following bonds: Ca and O, C and O, K and O, O and O, and N and O.

d. Arrange the covalent bonds in order of decreasing polarity.

Consider an ion with the symbol X²⁺ formed from a representative element.

b. What is the Lewis symbol of the element?

Consider an ion with the symbol X²⁺ formed from a representative element.

c. If X is in Period 3, what is the element?

Consider an ion with the symbol X²⁺ formed from a representative element.

d. What is the formula of the compound formed from X and the nitride ion?

Consider an ion with the symbol Y^3- formed from a representative element.

b. What is the Lewis symbol of the element?

Consider an ion with the symbol Y^3- formed from a representative element.

c. If Y is in Period 3, what is the element?

One of the ions of tin is tin(IV).

a. What is the symbol for this ion?

One of the ions of tin is tin(IV).

b. How many protons and electrons are in the ion?

Draw the Lewis structure for each of the following:

b. H₂NOH (N is the central atom)

Draw the Lewis structure for each of the following:

a. H₃COCH₃ (the atoms are in the order C O C)

Select the more polar bond in each of the following pairs:

c. Br―Cl or S―Cl

Show the dipole arrow for each of the following bonds:

a. Si―Cl

Calculate the electronegativity difference and classify each of the following bonds as nonpolar covalent, polar covalent, or ionic:

a. Si and Cl

Calculate the electronegativity difference and classify each of the following bonds as nonpolar covalent, polar covalent, or ionic:

b. C and C

Calculate the electronegativity difference and classify each of the following bonds as nonpolar covalent, polar covalent, or ionic:

c. Na and Cl

Predict the shape and polarity of each of the following molecules, which have polar covalent bonds:

a. A central atom with three identical bonded atoms and one lone pair.

Identify the group number in the periodic table of X, a representative element, in each of the following ionic compounds:

a. XCl₃

Identify the group number in the periodic table of X, a representative element, in each of the following ionic compounds:

b. Al₂X₃

Identify the group number in the periodic table of X, a representative element, in each of the following ionic compounds:

b. X₂SO₃

Classify each of the following as ionic or molecular, and name each:

a. Li₂HPO₄

Classify each of the following as ionic or molecular, and name each:

b. Cl₂O₇

Complete the Lewis structure for each of the following:

a.

Identify the errors in each of the following Lewis structures and draw the correct formula:

c.