Chemical Changes

Have you ever watched fireworks explode in the sky with bright colors and loud booms? Chemical changes cause these effects.

A chemical change occurs when substances combine or break apart to form new substances with different properties.

When fireworks explode, chemicals inside them burn, releasing heat, light, and gases, creating glowing patterns in the sky.

A metal bike left in the rain can turn reddish-brown as rust forms when iron reacts with water and oxygen.

Another example is burning wood in a campfire. As it burns, it produces heat, light, smoke, and ash—none of which can turn back into wood.

So, how do we know when a chemical change has occurred? Look for clues like color changes, bubbles, unusual odors, or the release of heat and light.

Unlike melting ice, which can return to water, most of the chemical changes are irreversible.

Chemical changes are everywhere—from the food we cook to the batteries that power our devices. Can you spot more examples around you?