Question

multiple choice 1 point
use the given ion charges to determine the formula for aluminum sulfate.
3+\t2-
al?\t(so4)?

o al(so4)2
o al2(so4)3
o al(so4)
o al3(so4)2

Explanation:

Step1: Determine charge - balance principle

The compound must be electrically neutral.

Step2: Identify ion charges

Aluminum ion ($Al^{3 + }$) has a charge of + 3 and sulfate ion ($SO_4^{2 - }$) has a charge of - 2.

Step3: Find least - common multiple

The least - common multiple of 3 and 2 is 6.

Step4: Calculate ion numbers

To balance the charges, we need 2 aluminum ions ($2\times3 = 6$) and 3 sulfate ions ($3\times2=6$). So the formula is $Al_2(SO_4)_3$.

Answer:

B. $Al_2(SO_4)_3$