Reactions with Bases and Displacement Reactions

The video tutorial explores the safety of train travel and the maintenance of railway tracks, focusing on the thermite reaction used to repair cracks. It explains metal reactivity and displacement reactions, using examples like iron displacing copper. The tutorial also covers how alkalis react with metals, particularly aluminum, and briefly touches on non-metals' reactions with bases.

What is the primary purpose of the thermite reaction in railway maintenance?

• To clean the railway tracks

• To lubricate the tracks

• To weld cracks in the tracks

• To paint the railway tracks

Which metal can displace copper from copper sulfate?

• Zinc

• Iron

• Magnesium

• Aluminum

What is observed when an iron nail is placed in a copper sulfate solution?

• The solution remains unchanged

• Copper is deposited on the nail

• The solution turns blue

• The nail dissolves

What color change indicates the formation of iron sulfate in the solution?

• No color change

• Pale green to blue

• Green to pale green

• Blue to green

Which metal is an exception and reacts with alkalis?

• Magnesium

• Aluminum

• Copper

• Iron

What gas is released when aluminum reacts with sodium hydroxide?

• Oxygen

• Nitrogen

• Hydrogen

• Carbon dioxide

What compound is formed when aluminum reacts with potassium hydroxide?

• Potassium nitrate

• Potassium sulfate

• Potassium aluminate

• Potassium chloride