Solubility and Properties of Sulfides

The video explores the solubility of zinc sulfide (ZnS) in water. It begins by noting the absence of zinc and sulfide ions in a basic solubility list, explaining that sulfides of all metals are generally insoluble, except for certain group one metals and ammonium sulfide. The video further explains that zinc, being a transition metal, forms insoluble sulfides. This is confirmed using a solubility table, which shows zinc sulfide as insoluble. The video concludes by reiterating that zinc sulfide does not dissolve in water, with any dissociation being negligible.

What is the chemical formula for zinc sulfide?

• ZnO

• ZnS

• ZnCl2

• ZnSO4

Which of the following metals form insoluble sulfides in water?

• Sodium

• Potassium

• Ammonium

• Zinc

According to the solubility rules, which group of metals have sulfides that are generally insoluble?

• Alkali metals

• Noble gases

• Alkaline earth metals

• Transition metals

Which of the following is an exception to the rule that sulfides are insoluble in water?

• Zinc sulfide

• Sodium sulfide

• Iron sulfide

• Copper sulfide

What does the solubility table indicate about zinc sulfide?

• It is highly soluble

• It is reactive

• It is slightly soluble

• It is insoluble

What is the charge on the zinc ion in zinc sulfide?

• +2

• -2

• -1

• +1

What is the charge on the sulfide ion in zinc sulfide?

• +1

• +2

• -1

• -2

What is the significance of the negligible amount of zinc sulfide that dissolves in water?

• It indicates high solubility

• It is considered significant

• It is considered negligible

• It indicates reactivity