1. It’s made of metal (usually iron, aluminum, or stainless steel).

   • The soleplate (the flat bottom part that touches your clothes) is made of metal, which is a good conductor of heat.

   • This lets the heat from the heating element spread evenly across the whole surface.

2. It transfers heat efficiently to clothes.

   • When electricity flows through the heating element inside the iron, it gets hot.

   • The metal soleplate quickly absorbs and conducts that heat to your clothes, making it easy to remove wrinkles.

3. It stays warm for a while.

   • Metals like iron also have a good heat capacity, so they can store and maintain heat, keeping the iron hot enough to use for several minutes.

So the electric iron conducts heat well because its metal soleplate spreads the heat evenly from the heating element to your clothes.

• Metals (like copper or iron) have free-moving electrons that carry heat quickly.

• Plastic doesn’t have free electrons, so heat can’t move easily through it.

🔹 2. Plastic’s molecules are tightly bonded

• In plastics, the atoms are held together by strong covalent bonds and arranged in a way that doesn’t let vibrations pass easily.

• When one part of the plastic gets hot, the heat doesn’t spread quickly to the rest.

🔹 3. It’s an insulator

• Because plastic doesn’t let heat pass through easily, it’s called a thermal insulator.

• That’s why plastic handles are used on pots, kettles, and irons — they stay cool even when the metal part is hot.

💡 Example:

If you pour hot water into a plastic bag, the bag might melt, but the heat won’t spread evenly through it — it mostly stays near where the water touches.

In short:
Plastic bags are bad conductors of heat because they lack free electrons and their molecules don’t transfer vibrations easily, so heat moves through them very slowly.