2. What happened to the lighted candle after it is covered with glass? Explain combustion. What is rusting? How did you define the amount of rust form in an iron?
Answer (1)
1. What happened to the lighted candle after it is covered with glass?When a lighted candle is covered with a glass, the flame will eventually go out. This happens because the glass limits the supply of oxygen inside. Combustion (burning) requires oxygen, so when the oxygen inside the glass is used up, the candle can no longer keep burning and the flame extinguishes.2. Explain combustion.Combustion is a chemical reaction between a fuel and oxygen that produces heat and light. It usually involves burning a substance like wood, candle wax, or gasoline, and it releases energy in the form of heat and often a flame. The general reaction is (Fuel + Oxygen → Carbon dioxide + Water + Heat + Light)3. What is rusting?Rusting is the process where iron reacts with oxygen and moisture (water) in the air to form a reddish-brown flaky substance called rust (iron oxide). It is a type of corrosion that weakens the metal.4. How do you define the amount of rust formed on iron? Explain briefly.The amount of rust formed on iron can be defined by observing the surface area covered by rust, the thickness of the rust layer, or by measuring the weight loss of the iron due to corrosion. More rust means more iron has reacted and corroded.
