**Correct Option: C. Mass** ### Explanation of Why the Answer is Correct: In chemistry, fundamental properties of matter are those characteristics that define the nature of substances and are intrinsic to them. Among the options provided, mass is considered a fundamental property of matter for several reasons: 1. **Definition of Mass**: Mass is a measure of the amount of matter in an object. It is a scalar quantity and is typically measured in grams (g) or kilograms (kg). Mass is a fundamental property because it does not change regardless of the object's location (e.g., whether it is on Earth or in space). 2. **Conservation of Mass**: One of the key principles in chemistry is the law of conservation of mass, which states that mass is neither created nor destroyed in a chemical reaction. This principle is foundational to stoichiometry and helps chemists understand how substances interact and transform during reactions. 3. **Measurement and Units**: Mass can be measured using a balance, and it is a critical factor in determining the quantities of reactants and products in chemical equations. This makes it essential for calculations in chemistry, such as determining molar mass and performing conversions between moles and grams. 4. **Relation to Other Properties**: While other properties like volume, color, and temperature can provide useful information about a substance, they are not fundamental in the same way that mass is. For example, volume can change with temperature and pressure, and color is a subjective observation that can vary based on lighting conditions. ### Explanation of Why the Other Options Are Wrong or Weaker: - **A. Color**: Color is a physical property that can help identify substances but is not fundamental. It can change based on various factors, such as concentration, temperature, and the presence of impurities. Therefore, it is not a reliable measure of the amount of matter present. - **B. Volume**: Volume is the amount of space that a substance occupies. While it is an important property in chemistry, it is not fundamental because it can change with temperature and pressure (e.g., gases expand when heated). Volume is also dependent on the shape of the container, making it less intrinsic to the substance itself. - **D. Temperature**: Temperature is a measure of the average kinetic energy of the particles in a substance. It is crucial for understanding the behavior of matter, especially in terms of phase changes and reaction rates. However, like volume, temperature is not a fundamental property because it can vary based on external conditions and does not define the substance itself. ### Summary of Key Points: - **Mass** is a fundamental property of matter, representing the amount of matter in an object and is invariant regardless of location. - The **law of conservation of mass** is a cornerstone of chemical reactions, emphasizing the importance of mass in stoichiometry. - Other properties like **color**, **volume**, and **temperature** are important but are not fundamental as they can change under different conditions. - Understanding mass is essential for accurate measurements and calculations in chemistry, making it a foundational concept in the field.