Section 2: Types of Mixtures

What is a solution?

• A homogeneous mixture with small particles that cannot be seen with a microscope

• A heterogeneous mixture with large particles that settle at the bottom

• A mixture of particles larger than a solution but too light to settle

• A mixture that always scatters light

Answer explanation

A solution is a homogeneous mixture with small particles that cannot be seen with a microscope.

Which of the following is an example of a solution?

• Fog

• Vinegar

• Chocolate milk

• Italian salad dressing

Answer explanation

Vinegar is an example of a solution because it is a homogeneous mixture of two or more substances where one substance is dissolved in another.

What is a colloid?

• A heterogeneous mixture with visible particles that settle

• A mixture of particles larger than a solution but too light to settle

• A homogeneous mixture with small particles

• A mixture that does not scatter light

Answer explanation

A mixture of particles larger than a solution but too light to settle

What is the Tyndall effect?

• The separation of particles in a suspension

• The dissolving of substances in a solution

• The scattering of light by particles in a colloid

• The process of particles settling at the bottom of a container

Answer explanation

The Tyndall effect is the scattering of light by particles in a colloid, distinguishing it from solutions where light passes through without scattering.

Which of the following is an example of a colloid?

• Vinegar

• Italian salad dressing

• Chocolate milk

• Fog

Answer explanation

Fog is an example of a colloid because it consists of small liquid droplets suspended in the air, making it a heterogeneous mixture.

What type of mixture is Italian salad dressing?

• Suspension

• Homogeneous mixture

• Colloid

• Solution

Answer explanation

Italian salad dressing is a suspension because it contains visible particles that settle over time and need to be shaken before use.

What happens to the particles in a suspension over time?

• They dissolve completely

• They remain evenly distributed

• They scatter light

• They settle to the bottom

Answer explanation

Particles in a suspension settle to the bottom over time due to gravity, leading to the formation of sediment. This process is known as sedimentation.

Which of the following is NOT a characteristic of a solution?

• Homogeneous mixture

• Particles cannot be seen with a microscope

• One or more substances dissolved in another

• Particles settle at the bottom

Answer explanation

Particles settle at the bottom is NOT a characteristic of a solution as solutions are homogeneous mixtures where particles do not settle.

Which mixture requires shaking before use?

• Solution

• Homogeneous mixture

• Colloid

• Suspension

Answer explanation

Suspension is the mixture that requires shaking before use due to the particles settling at the bottom. Shaking helps to distribute the particles evenly throughout the mixture.

Which of the following is an example of a suspension?

• Chocolate milk

• Hydrogen peroxide

• Vinegar

• Fog

Answer explanation

Chocolate milk is an example of a suspension because it consists of solid particles (cocoa) dispersed in a liquid (milk), which do not dissolve completely.