Matter undergoes a change. The changes are of two types: Physical and chemical change. A physical change is a change that involves only a change in the physical state of matter. Its chemical properties remain the same. Usually increasing the temperature or applying pressure or both bring about a physical change. On reversing the condition, that is reducing the temperature or reducing the pressure or both, the original state of matter is restored. In other words, physical changes are reversible.

A chemical change is a change that involves a change in the chemical composition of matter. A new substance is formed. In a chemical change, new chemical and physical properties of the substance are formed. In a chemical change, the chemical and physical properties of the substance formed will be different from the original substance.

In a chemical change the properties that change are:

• A. Chemical only
• B. Physical only
• C. Both chemical and physical
• D. Neither physical nor chemical

Changes in matter can be categorized into two main types: physical changes and chemical changes. Understanding these differences is essential for grasping how substances interact and transform.

Physical Changes

A physical change affects only the physical state of a substance without altering its chemical composition. Common characteristics include:

• Reversibility: These changes can often be reversed. For example, melting ice can turn back into water when cooled.
• Conditions: Physical changes typically occur due to changes in temperature or pressure.

Chemical Changes

In contrast, a chemical change results in the formation of one or more new substances with different chemical and physical properties. Key points include:

• New Substances: A chemical reaction produces substances that differ from the original materials.
• Irreversibility: Many chemical changes are not easily reversible, such as burning wood to create ash.

Identifying Changes

When considering the properties that change during a chemical reaction, the answer is:

C. Both chemical and physical

This means that in a chemical change, both the chemical composition and the physical properties of the substance are altered.