Ionic Compounds and Cobalt Chemistry

The video tutorial explains how to write the formula for cobalt(III) chloride by identifying the elements cobalt and chloride on the periodic table. It discusses the ionic charges of these elements and uses the crisscross method to balance the charges, ensuring a neutral compound. The tutorial concludes by verifying the formula and confirming its correctness.

What is the chemical symbol for cobalt?

• Co

• Cl

• Ca

• Cu

Which of the following is a non-metal in cobalt(III) chloride?

• Cobalt

• Calcium

• Copper

• Chlorine

What is the ionic charge of cobalt in cobalt(III) chloride?

• 3+

• 4+

• 2+

• 1+

How many chloride ions are needed to balance the charge of one cobalt ion in cobalt(III) chloride?

• 1

• 4

• 3

• 2

What method is used to determine the subscripts in the formula of cobalt(III) chloride?

• Substitution method

• Balancing method

• Crisscross method

• Cross-multiplication

In the crisscross method, what happens to the charges of the ions?

• They are ignored

• They are crisscrossed

• They are subtracted

• They are added

What is the net charge of cobalt(III) chloride?

• 1+

• 0

• 2-

• 3+

How many chlorine atoms are present in the formula of cobalt(III) chloride?

• 4

• 2

• 1

• 3

What is the final chemical formula for cobalt(III) chloride?

• CoCl

• CoCl2

• Co3Cl

• CoCl3