Cobalt II Phosphate Solubility Concepts

The video explores the reaction of cobalt 2 phosphate with water, focusing on its solubility. Cobalt 2 phosphate is mostly insoluble in water, falling to the bottom of the test tube. However, a small amount dissolves, forming cobalt and phosphate ions. The video explains how to write the equation for this minor dissolution and discusses the solubility rules that apply. The conclusion reiterates that most of the solid remains undissolved.

What is the main objective of the video regarding cobalt II phosphate and water?

• To observe the reaction speed

• To measure the temperature change

• To find out if cobalt II phosphate dissolves in water

• To determine the color change when mixed

According to solubility rules, what is the general solubility of phosphates in water?

• All phosphates are soluble

• All phosphates are insoluble

• Most phosphates are insoluble

• Most phosphates are soluble

What happens to cobalt II phosphate when it is placed in water?

• It completely dissolves

• It remains mostly solid

• It reacts vigorously

• It changes color

What ions are formed from the small amount of cobalt II phosphate that dissolves?

• Cobalt III ions and hydroxide ions

• Cobalt II ions and phosphate ions

• Cobalt III ions and phosphate ions

• Cobalt II ions and hydroxide ions

How do the charges balance in the dissolved ions of cobalt II phosphate?

• One cobalt II ion balances with one phosphate ion

• Four cobalt II ions balance with one phosphate ion

• Three cobalt II ions balance with two phosphate ions

• Two cobalt II ions balance with three phosphate ions

What notation is used to indicate that ions are dissolved in water?

• aq for aqueous

• g for gas

• l for liquid

• s for solid

What is the primary form of cobalt II phosphate in water?

• Solid at the bottom

• Dissolved ions

• Colored solution

• Gas bubbles

Where is water sometimes written in the chemical equation for this reaction?

• Below the arrow

• Above the arrow

• Next to the reactants

• Next to the products

What is the overall conclusion about cobalt II phosphate's behavior in water?

• It is highly soluble

• It is mostly insoluble

• It reacts to form a new compound

• It evaporates quickly

What is the significance of the small amount of cobalt II phosphate that dissolves?

• It changes the color of the solution

• It demonstrates partial solubility

• It forms a significant amount of ions

• It causes a temperature increase