Vinegar and baking soda are mixed together. They form a new substance, carbon dioxide.
Water is heated and turns into steam.
A glass falls to the ground and breaks into small pieces.
Baking soda is mixed with water.
Sand and salt are mixed together in a bowl.
A match is lit.
An iron bar rusts when it is left out in the rain.
A teaspoon of sugar is dissolved in a cup of water.
Water is frozen.
A piece of chalk is ground into dust.
An aluminum pot is placed on a stove and heats up.
An iron rod gets magnetized.
You cut your knee and put hydrogen peroxide on the cut. The hydrogen bubbles up when it comes into contact with your bodily fluids. It gives off pure oxygen gas.
Lemon juice is adding to a baking soda solution. Carbon dioxide gas is given off.