Question

a potassium iodide compound is represented by which formula?
a k₂i
b k₂i₂
c ki
d ki₂

Explanation:

Step1: Determine ion charges

Potassium (K) has a charge of \( +1 \) (group 1 metal), iodide (I⁻) has a charge of \( -1 \) (halide ion).

Step2: Balance charges in formula

To balance charges, the number of \( K^+ \) and \( I^- \) ions must be such that total positive charge = total negative charge. Let the formula be \( K_xI_y \). Then \( x(+1) + y(-1) = 0 \), so \( x = y \). The simplest ratio is \( 1:1 \), so the formula is \( KI \) (option C, assuming C is \( KI \); note: check the original options—if C is \( KI \), that's correct).

Answer:

C. \( KI \) (assuming option C is \( KI \); adjust based on exact option labels, but the correct formula for potassium iodide is \( KI \))