Copper Compounds and Ionic Charges

The video tutorial explains how to write the formula for copper(I) sulfide using the periodic table. It covers the identification of copper and sulfur, their charges, and the formation of an ionic compound. The tutorial introduces the crisscross method to balance charges and derive the correct formula, Cu2S. The process is verified to ensure the net charge is zero, confirming the accuracy of the formula.

What is the symbol for copper on the periodic table?

• Co

• Cu

• Ca

• C

What type of compound is formed between a metal and a non-metal?

• Covalent

• Ionic

• Hydrogen

• Metallic

What is the charge of copper in copper(I) sulfide?

• 1-

• 1+

• 2-

• 2+

What is the charge of sulfur in copper(I) sulfide?

• 1+

• 2-

• 2+

• 1-

Which method is used to balance the charges in copper(I) sulfide?

• Crisscross method

• Substitution method

• Elimination method

• Balancing method

What is the formula for copper(I) sulfide?

• CuS2

• CuS

• Cu2S

• Cu2S2

How do you verify the formula for copper(I) sulfide?

• By checking the color

• By checking the charges add up to zero

• By checking the melting point

• By checking the density

What is the net charge of a correctly balanced ionic compound?

• Variable

• Zero

• Negative

• Positive