Question

Change of apple's colour into brown is a chemical change. Explain why?

Answer 1

An apple turning brown is a chemical change that occurs due to the oxidation of compounds in the apple when exposed to air, creating new substances that have a different color and flavor.

Step-by-step explanation:

The change of an apple's color into brown is a chemical change because it involves the reaction of oxygen in the air with certain compounds in the apple flesh. This process is known as oxidation, which alters the chemical structure of those compounds and produces new substances. Color changes, such as the browning of an apple, are indicators of chemical changes, similar to how rust forms on iron by the reaction of iron and oxygen to produce iron oxide (Fe2O3). Just like cooking red meat or a banana turning brown, the apple's browning signifies a transformation in the chemical composition of the apple, creating different properties like color and flavor that distinguish it from the original unreacted apple.

Answer 2

The browning of an apple is a chemical change due to the oxidation process that produces new, brown-colored compounds when the apple is exposed to air. This changes the apple's properties and indicates a transformation at the molecular level.

Step-by-step explanation:

The change of an apple's color to brown is a chemical change because it involves the process of oxidation. When an apple is cut and exposed to oxygen in the air, the iron-containing compounds in the apple react with the oxygen to form a new substance, which results in the brown color. This color change is an indication of a chemical change, as the apple's flesh undergoes a transformation at the molecular level, with the creation of new compounds such as o-quinones, which produce the brown color. This change in composition brings about a change in the apple's properties like color, taste, and nutritional content. Additionally, since new substances are formed and bonds between atoms are broken and/or formed, it's clear evidence that a chemical change has occurred.

Examples of chemical changes include the rusting of iron (Fe + O2 → Fe2O3), combustion of materials, and cooking of food, all of which result in substances with different properties than the ones present before the change. Unlike physical changes, chemical changes often result in matter that has a completely different molecular composition and are usually more challenging to reverse.