1. Warm-up
1. A student observes a sample of salt water. Is this sample a mixture or a pure substance? Choose the best answer and explanation.
A. A pure substance, because it has the same appearance throughout.
B. A homogeneous mixture, because it has the same appearance throughout.
C. A pure substance, because it consists of visibly different substances
D. A homogeneous mixture, because it consists of visibly different substances. 2.
2. The mixture might contain small pieces of metal, such as iron

2. Warm-up
1. A mixture is what you get when you combine two substances in such a way that no chemical reaction occurs between the components. A solution is a mixture that looks exactly the same everywhere. Which of these mixtures is not a solution?
A. a glass of apple juice C. a chocolate chip cookie
B. a mixture of sugar and water D. a mixture of salt and water
2. Steel is a metal that is made from iron and carbon. When steel is produced, iron and carbon are melted and blended together. The iron and carbon do not chemically react with each other. After the steel was made 20 samples were tested. Each sample contained 98% iron and 2% carbon. Which of the following terms best describes steel?
A. compound C. heterogeneous mixture
B. element D. homogenous mixture

3. Warm-up
1) What is the simplest type of matter, made up of one type of atom?
A. proton B. neutron C. element D. molecule
2) Which of the following is an example of a container that is filled with a pure substance instead of a mixture?
A. a tire filled with air B. a glass filled with chocolate milk
C. a jar filled with salt water D. a balloon filled with helium
3) Compare and contrast mixtures and compounds. Which statement is true about mixtures and compounds?
A. Mixtures and compounds are the same throughout.
B. Mixtures and compounds are made of two or more elements in a definite proportion.
C. Mixtures must be separated by chemical methods and compounds by physical methods
D. Mixtures contain two or more elements physically combined and compounds contain two or more elements chemically combined

4. Warm-up 8-17-18 14. What state of matter is pictured above? GAS
15. If energy were added, how would the particles be arranged? A, PLASMA
16. If energy was taken away, how would the particles be arranged? C, LIQUID