Aluminum Sulfate and Ionic Compounds

The video tutorial explains how to write the formula for aluminum sulfate. It begins by identifying aluminum on the periodic table and recognizing sulfate as a polyatomic ion. The tutorial discusses the charges of aluminum and sulfate ions and uses the crisscross method to balance these charges, resulting in the formula Al2(SO4)3. The video concludes by verifying the formula to ensure a net charge of zero.

What is the symbol for aluminum on the periodic table?

• Al

• Au

• Ag

• Am

Which of the following is a polyatomic ion?

• Sulfur

• Sulfate

• Oxygen

• Aluminum

What is the charge of the sulfate ion?

• 2+

• 3-

• 2-

• 1-

What is the ionic charge of aluminum?

• 4+

• 1+

• 3+

• 2+

What method is used to balance the charges in aluminum sulfate?

• Substitution

• Cross-multiply

• Crisscross

• Elimination

Why do we use parentheses around the sulfate ion in the formula?

• To indicate it is a metal

• To separate it from aluminum

• To show it is a polyatomic ion

• To highlight its charge

How many sulfate ions are present in aluminum sulfate?

• 1

• 2

• 3

• 4

What is the total positive charge contributed by aluminum in the compound?

• 12+

• 9+

• 6+

• 3+

What is the net charge of aluminum sulfate?

• 1+

• 2-

• 0

• 3+

What is the final formula for aluminum sulfate?

• Al2(SO4)2

• Al3(SO4)2

• Al(SO4)3

• Al2(SO4)3