Mixtures and Pure Substances

Dry ice is solid carbon dioxide, or CO2. Dry ice may be used as a cooling agent and contains two oxygen atoms bonded to a carbon atom. Dry ice is a ___________________ .

• pure substance

• mixture

Instant coffee is made by dissolving a powder in hot water. Instant coffee is a ___________________ .

• pure substance

• mixture

Baking soda is the common name for sodium bicarbonate, or NaHCO3. It can be produced through chemical reactions involving carbon dioxide and sodium hydroxide.

• pure substance

• mixture

Cake batter is a substance that may contain flour, eggs and sugars mixed by hand or with an electric mixer. Cake batter is a ___________________ .

• pure substance

• mixture

Blood is a fluid found in the bodies of humans and other animals. It can be physically separated into plasma, red blood cells and white blood cells. Blood is a ___________________

• pure substance

• mixture

Methane contains one atom of carbon and four atoms of hydrogen that are chemically bonded. It is a main component of natural gas. Methane is a ___________________ .

• pure substance

• mixture

Chalk is a mineral found in rocks. It contains carbon, oxygen and calcium atoms. Chalk is a ___________________ .

• element

• compound

Nickel has the chemical symbol Ni and atomic number 28. It is a silvery-white metal and cannot be broken down physically or chemically into a more simple substance. Nickel is a ___________________ .

• element

• compound

Ammonia is a colorless gas with the formula NH3. Ammonia contains hydrogen and nitrogen and cannot be broken down physically. Ammonia is a ___________________ .

• element

• compound

The noble gases are a group of six substances with similar properties. They are odorless, colorless gases with low reactivity. They are group 18 on the periodic table. Each noble gas is a(n) _______ .

• element

• compound

• heterogeneous mixture

• homogenous mixture/solution