We can see the three states of matter—solids, liquids, and gases—every day around us. Let's break them down with some simple examples.

Solids:

• Ice: When water gets really cold, like at 0°C (32°F), it turns into ice. Ice is a solid, and it floats on water because it is less dense, with a density of about 0.92 grams per cubic centimeter.
• Iron: Metals like iron are also solids. They are heavy, with a density around 7.87 grams per cubic centimeter, and keep their shape at room temperature.

Liquids:

• Water: At about room temperature (around 20°C or 68°F), water is a liquid. It has a density of about 1 gram per cubic centimeter. Water is super important for life since about 70% of the Earth is covered in it.
• Oil: Oils like olive oil are lighter than water, with a density of around 0.91 grams per cubic centimeter. That's why oil floats on top when you mix it with water.

Gases:

• Oxygen: At room temperature, oxygen is a gas. It has a very low density of about 0.00143 grams per cubic centimeter. We need oxygen to breathe!
• Carbon Dioxide: This gas is a bit heavier, with a density of around 0.00198 grams per cubic centimeter. It’s produced when we breathe out and when things burn.

By looking at these examples, we can better understand how solids, liquids, and gases behave and what makes them unique.