Question

Which of the following is a mixture?

salt water

carbon dioxide

water vapor

oxygen gas

Answer 1

Answer: Salt Water

Explanation: The combination of two different substances which are not chemically identical is known as the mixture.

Mixture are of two types - homogeneous mixture and Heterogeneous mixture.

Homogeneous Mixture are the those in which which the substances are mixed well with each other so that only one phase appears like salt in water.

Heterogeneous Mixture are those in which two separate phases occur like oil in water.

Thus carbon dioxide, water vapor and oxygen gas are not mixture as carbon reacts with oxygen chemically to form CO2 . Similarly hydrogen gas and oxygen gas combines chemically to form water vapor. Oxygen is the diatomic elemental gas.

Moreover no chemical reaction takes place between the subsatnces when mixture is formed.

Answer 2

Answer: Option (a) is the correct answer.

Step-by-step explanation:

A substance in which two or more elements are mixed together but these substances do not combine chemically to each other is known as a mixture.

For example, salt in water is a mixture as salt completely dissolves in water.

Whereas in carbon dioxide, carbon atom reacts chemically with oxygen atom. So, it is not a mixture.

Similarly, water vapor and oxygen gas are both compounds as they contain atoms which are present in similar composition.

Thus, we can conclude that out of the given options salt water is a mixture.