Sodium Phosphide Charge Balancing

The video tutorial explains how to write the chemical formula for sodium phosphide by examining the periodic table to identify sodium (Na) and phosphorus (P). It discusses the need to balance charges in ionic compounds, as sodium has a +1 charge and phosphorus a -3 charge. By adjusting the subscript, the formula Na3P is derived. The crisscross method is used to verify the formula, ensuring the charges are balanced. The video concludes with a summary of the process.

What are the symbols for sodium and phosphorus as found on the periodic table?

• S and Ph

• N and P

• Na and P

• So and Ph

Why is it necessary to balance charges in an ionic compound?

• To make the compound dissolve in water

• To make the compound more colorful

• To ensure the compound is stable

• To increase the compound's weight

What is the charge of a sodium ion?

• -2

• +1

• -1

• +2

How many sodium ions are needed to balance one phosphorus ion?

• One

• Two

• Three

• Four

What is the correct formula for sodium phosphide after balancing the charges?

• Na3P

• Na2P

• Na4P

• NaP

What method can be used to verify the formula of sodium phosphide?

• Reverse method

• Double-check method

• Crisscross method

• Cross-check method

What happens to the charges in the final formula of sodium phosphide?

• They are ignored

• They are balanced and removed

• They are increased

• They are doubled