An element from Group 13 bonds with an element from Group 17. Which formula correctly depicts the correct chemical formula for elements from these two groups?

Question

Responses
A AlCl3AlCl 3
B B3IB 3 I
C BFBF
D BrGa3BrGa 3
Question 2
PART B
Based on your answer to Part A, what is the oxidation number for the elements that combined?
Responses
A -3 & +1-3 & +1
B +1 & -1+1 & -1
C +1 & -3+1 & -3
D +3 & -1

Answer 1

To solve these questions, we need to identify the common bonding behavior of Group 13 and Group 17 elements.

Question 1

Group 13 includes elements like aluminum (Al) and gallium (Ga), while Group 17 includes halogens such as chlorine (Cl), bromine (Br), and iodine (I). When a Group 13 element bonds with a Group 17 element, the typical bonding ratio is that the Group 13 element has a +3 oxidation state and the Group 17 usually has a -1 oxidation state. Therefore, to balance charges:

• Aluminum forms AlCl₃ (3 chlorides for 1 aluminum),
• Gallium forms GaI₃ (3 iodides for 1 gallium).

Among the given options, AlCl₃ is the correct formula.

So the answer to Question 1 is: A. AlCl₃

Question 2

From the bonding described, the oxidation states are:

• For aluminum (Group 13) = +3
• For chlorine (Group 17) = -1

So the answer to Question 2 based on the oxidation numbers is: D. +3 & -1