Scope Assessment-Teks 6.6B: Pure Substances and Mixtures

A student copied down notes from their science teacher about three different types of substances. Somehow, the part of the page with the substance names got removed from the notebook. Can you help them correctly identify the substance names for the following three substances? Substance 1: A substance with uniform appearance that can easily be separated by physical means. Example: Lemonade, salt water Substance 2: A substance with a varied appearance that can be easily separated by physical means. Example: Trail mix, fruit salad Substance 3: A substance with uniform appearance that cannot be separated by physical means. Example: Helium, salt

• Substance 1: Homogeneous mixture; Substance 2: Pure substance; Substance 3: Heterogeneous mixture

• Substance 1: Homogeneous mixture; Substance 2: Heterogeneous mixture; Substance 3: Pure substance

• Substance 1: Heterogeneous mixture; Substance 2: Pure substance; Substance 3: Homogeneous mixture

• Substance 1: Pure substance; Substance 2: Heterogeneous mixture; Substance 3: Homogeneous mixture

Students were investigating mixtures. During the investigation, they were asked to mix four different types of substances. Which experiment result would show that a heterogeneous mixture was created?

• After mixing, salt was not able to be seen

• After mixing, food coloring was found uniformly

• After mixing, chocolate chips could be seen

• After mixing, oil and water remained separate

When panning for gold, a miner scoops up gravel, rocks, and dirt, and then washes the mixture with water, leaving the gold behind. What is one reason the gold is easily separated from the gravel, rocks, and dirt?

• The gold is easily separated because the mixture is a pure substance. This means it is easily separated by physical means.

• The gold is easily separated because the mixture is a homogeneous mixture. This means it is easily separated by physical means.

• The gold is easily separated because the mixture is a heterogeneous mixture. This means it is easily separated by physical means.

• The gold is easily separated because the mixture is a solution. This means it is easily separated by physical means.

Which of the following is NOT an example of a homogeneous mixture (solution)?

• Sodium and chlorine chemically combine to create salt.

• Water and lemonade powder are mixed to create lemonade.

• Salt is dissolved in water to create salt water.

• Milk is poured into coffee and mixed.

Which of the following is NOT a method used to determine if a substance is a mixture or a pure substance?

• Chemical separation

• Evaporation

• Straining with a sieve

• Tweezers

6. Select the property that is shared by both homogeneous and heterogeneous mixtures.

• They can be separated by physical means.

• They have a uniform composition throughout.

• They are pure substances.

• They have fixed melting and boiling points.

Refer to the table below and select two correct answers.

• Uniform physical appearance

• Ability to easily separate

• Composed of two or more substances

• Inability to easily separate

• Inconsistent physical appearance

The table below lists different types of substances. Identify the type of substance described in each column.

• Homogeneous Mixture

• Pure Substance

• Heterogeneous Mixture

• Heterogeneous Mixture

• Pure Substance

• Homogeneous Mixture

Which sections of the circle graph provided are considered pure substances?

• Substance 1 and 2

• Substance 2 and 3

• Substance 3 and 4

• Substance 1 and 3

Which statement best explains the answer to Part A?

• pure substance is not uniform in appearance and can easily be separated by physical means.

• pure substance is uniform in appearance and can easily be separated by physical means.

• pure substance is uniform in appearance and cannot easily be separated by physical means.

• pure substance is not uniform in appearance and cannot easily be separated by physical means.