Nickel and gold combine to make white gold. Which statement best describes white gold?

• A. White gold is a compound formed by a chemical reaction between gold and nickel.
• B. White gold is a pure substance consisting only of gold atoms.
• C. White gold is a mixture in which gold and nickel retain their individual properties and can be easily separated.
• D. White gold is a homogeneous alloy of gold and nickel.

Answer: (D)

Verified step by step guidance

1. Understand the difference between compounds, pure substances, mixtures, and alloys: A compound is formed when elements chemically combine in fixed ratios, resulting in new substances with different properties.
2. Recognize that pure substances consist of only one type of atom or molecule, such as pure gold containing only gold atoms.
3. Identify that mixtures contain two or more substances physically combined, where each retains its own properties and can often be separated by physical means.
4. Learn that an alloy is a homogeneous mixture (solid solution) of two or more metals, where the metals are mixed at the atomic level and cannot be easily separated.
5. Conclude that white gold is best described as a homogeneous alloy of gold and nickel because it is a solid solution where the metals are combined physically but not chemically bonded as a compound.