1.

Use the Periodic Table of Elements to select the correct answer.

The sodium (Na) atom has [one, two, three, four] valance electrons and forms [an ionic, a covalent] bond with the chlorine (Cl).

2.

Use the Periodic Table of Elements to predict the balanced reaction of various elements.

Which best represents the balanced reaction of sodium and chlorine to form sodium chloride?

A. 2Na + 2Cl → 4NaCl

B. Na + Cl → NaCl

C. Na + 7Cl → NaCl₇

D. 2Na + 3Cl → Na₂Cl₃ 

3.

Sodium is more likely to naturally bond with chlorine than several of the other elements found in the same periodic group. Which of these statements would best explain why chlorine is more likely to react with sodium?

A. Sodium is a gas and the other elements are solids or liquids.

B. Sodium has a higher electronegativity than most of the elements in the group.

C. Other elements in the group are less common in nature.

D. Other elements in the group have a different number of valence electrons.

4.

Which factors would affect the rate at which this reaction occurs? Select all that apply.

A. concentration of HCl

B. concentration of H₂O

C. temperature of the products

D. temperature of the reactants

E. type of bonds between the products

F. type of bonds between the reactants

5.

The manufacturers of the calcium chloride increased the concentration of the HCl used in the reaction from 10% to 20%. Which of these statements would best represent the change in the reaction rate? 

A. The reaction rate would increase initially but would still level out to the same point.

B. The reaction rate would increase across the entire time the reaction occurs.   

C. The reaction rate would decrease initially but would eventually level out at the same point

D. The reaction rate would decrease across the entire time the reaction occurs. 

6. BCR

Use evidence to explain why the physical properties of the compounds sodium chloride and calcium chloride are so similar.