Reactivity and Properties of Metals

The video tutorial covers Chapter 4 on materials, focusing on metals and nonmetals. It begins with an overview of their properties, both physical and chemical, and explores how they react with oxygen, water, acids, and bases. The session includes exercises and questions to test understanding, followed by practical applications of metals and nonmetals. The tutorial concludes with additional questions and answers to reinforce the concepts learned.

Which of the following is a characteristic property of metals?

• Brittle

• Dull

• Sonorous

• Poor conductor of electricity

What type of oxide is formed when a metal reacts with oxygen?

• Neutral oxide

• Amphoteric oxide

• Basic oxide

• Acidic oxide

Which metal is more reactive than copper and can displace it from its salt solution?

• Gold

• Platinum

• Iron

• Silver

Which of the following statements is true about nonmetals?

• They are good conductors of heat.

• They are poor conductors of electricity.

• They are generally ductile.

• They are sonorous.

Why are aluminum foils used to wrap food items?

• They are poor conductors of heat.

• They are brittle and reactive.

• They are malleable and non-reactive to food.

• They are highly reactive.

Why are sodium and potassium stored in kerosene?

• They are non-reactive metals.

• They react vigorously with water and oxygen.

• They are poor conductors of electricity.

• They are used in jewelry making.

What happens when lemon pickle is stored in an aluminum utensil?

• The pickle remains fresh.

• The aluminum reacts with acids in the pickle.

• The pickle becomes more acidic.

• The aluminum utensil becomes shiny.

Which substance is used in thermometers?

• Gold

• Copper

• Mercury

• Iron

What is the result of burning charcoal in the presence of oxygen?

• Formation of sulfur dioxide

• Formation of basic oxide

• Formation of carbon dioxide

• Formation of hydrogen gas

What is the reason for the slight loss in weight of gold jewelry after polishing?

• The gold reacts with aqua regia.

• The gold is heated.

• The gold is melted.

• The gold is hammered.