Question

the lewis model predicts that the formula of a compound formed between bromine and aluminum is

• al₂br
• albr₃
• albr₂
• albr
• none of the above

Explanation:

Step1: Find valencies of elements

Aluminum (Al) has a valency of +3; bromine (Br) has a valency of -1.

Step2: Cross valencies for formula

Swap valencies: Al takes Br's 1, Br takes Al's 3. Formula is AlBr₃.

Answer:

A. AlBr₃