Lesson 3: What Are the Properties of Some Common Substances?

 The state of matter that does not have a definite shape or volume.

 The state of matter that has a definite volume but no definite shape

 The state of matter that has a definite shape and a definite volume

 Air is a mixture of gases. It does not have a formula.  78% of the air is nitrogen (N2).  21% of the air is oxygen (O2). All animals need oxygen.  A harmful form of oxygen is ozone (O3). It is found in Earth’s upper atmosphere where it absorbs some of the harmful energy from the sun and helps keep Earth at a constant temperature.

 Hydrogen is not found in the air, but it is the most common element in the universe. It combines with other elements to form hundreds of thousands of compounds.

 Noble gases: ◦ helium (He) ◦ neon (Ne) ◦ argon (Ar), ◦ krypton (Kr) ◦ xenon (Xe)  When added with electricity, each noble gas glows a different color.

 Two common gases that created from carbon are: ◦ carbon dioxide (CO2) ◦ methane (CH4)

 Water is the most common liquid on the planet.  It has a definite volume, but no definite shape.  Oceans cover 70% of Earth and make up 97% of all the water on Earth.  2% of Earth’s water is frozen in glaciers and ice caps.  Humans and animals can use 1% of Earth’s water, which is found in lakes, rivers, and groundwater.  Three states of water: liquid water, ice, and water vapor.

 Mercury stays liquid at a colder temperature than water.  It expands and contracts the same amount with every degree its temperature changes.  Early thermometers contained mercury, but it is not used anymore because mercury is poisonous.

 Carbon is the sixth most common element in the universe. It is a solid, so it has a definite shape and volume.  There are millions of compounds that contain carbon, including coal, petroleum, natural gas, and sugar.  The reason why carbon is present in so many compounds is because one carbon atom can combine with four other atoms at once.

 Carbon is the building block for all molecules of life on Earth.  98.8% of the human body is composed of only 6 elements – oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus.  One of the most complex molecules in your body is DNA. It is found in the nucleus of each cell and is a huge molecule that looks like a twisted ladder. DNA contains only five elements – carbon, hydrogen, oxygen, nitrogen, and phosphorus.

 Carbon Cycle Cartoon (4:37) xQ  Bill Nye Genes DNA (1:07) 8I&feature=related