What describes a compound?

What describes a compound?

• A. A single element
• B. A mixture of elements not chemically combined
• C. A chemical combination of two or more elements in fixed proportions
• D. A substance made of identical atoms only

Answer: (C)

A compound is formed when two or more elements join by chemical bonds in a definite, fixed ratio, creating a new substance with properties different from the elements themselves. The composition is fixed and can be written as a chemical formula that shows exactly how many atoms of each element are present. For example, water has hydrogen and oxygen in a 2:1 ratio, and table salt has sodium and chlorine in a 1:1 ratio. Because the elements are chemically bonded in fixed proportions, a compound cannot be separated into its elements by simple physical means; breaking it apart requires a chemical reaction. This distinguishes compounds from mixtures, where components are not bonded and can vary in proportion. It also clarifies why a substance made of identical atoms only is not a compound, since it consists of one element rather than two or more different elements.

A compound is formed when two or more elements join by chemical bonds in a definite, fixed ratio, creating a new substance with properties different from the elements themselves. The composition is fixed and can be written as a chemical formula that shows exactly how many atoms of each element are present. For example, water has hydrogen and oxygen in a 2:1 ratio, and table salt has sodium and chlorine in a 1:1 ratio. Because the elements are chemically bonded in fixed proportions, a compound cannot be separated into its elements by simple physical means; breaking it apart requires a chemical reaction. This distinguishes compounds from mixtures, where components are not bonded and can vary in proportion. It also clarifies why a substance made of identical atoms only is not a compound, since it consists of one element rather than two or more different elements.