Question

1. which is an example of a mixture of gases?

a. air
b. iron
c. rock
d. salad dressing

1. fill in the blank(s):

a combination of two or more substances in any proportion is called a

1. dissolving salt in water creates a homogeneous mixture.

a. true
b. false

1. which of the following lists two examples of mixtures?

a. lemonade; water
b. salad dressing; sugar
c. salt water; salt
d. air; gelatin

1. which is an example of a colloid?

a. salt water
b. salad dressing
c. homogenized milk
d. sugar and water

Explanation:

1.

Air is composed of nitrogen, oxygen, carbon - dioxide and other gases. Iron is an element, rock is a solid mixture (not gas - gas), salad dressing is a liquid - liquid or liquid - solid mixture.

By the definition of a mixture in chemistry, a combination of two or more substances in any proportion is called a mixture.

When salt is dissolved in water, the salt ions are evenly distributed throughout the water. A homogeneous mixture has a uniform composition throughout.

Answer:

A. air

2.