Question

Which statement is true about the substances in a mixture?

O They change their composition.
O They retain their chemical properties.
They always consist of the same element.
O They are always in the same state of matter.

Answer 1

Substances in a mixture retain their chemical properties, as they do not undergo any chemical changes when combined; instead, they coexist and can be separated by physical means.

Step-by-step explanation:

The true statement about the substances in a mixture is that they retain their chemical properties. When substances are mixed together to form a mixture, they do not undergo any chemical change; rather, they simply coexist alongside one another. For example, when salt is mixed with water to form a saline solution, the salt does not change its chemical makeup—it remains as sodium chloride, and water remains H2O.

Furthermore, mixtures can be separated back into their pure substances using physical methods because no new chemical bonds are formed in the mixture. For instance, the saline solution mentioned earlier can be separated by evaporation, where water is turned to vapor, leaving the salt behind.

This characteristic differentiation—substances in mixtures keeping their properties—is essential for understanding the distinction between mixtures and compounds, where compounds involve a chemical reaction that changes the chemical properties of the combined elements.