Which term is defined as the measure of mass per unit volume?

Which term is defined as the measure of mass per unit volume?

• A. Density
• B. Characteristic Property
• C. Mean
• D. Solvent

Answer: (A)

Mass per unit volume is called density. It tells you how much matter is packed into a given space and is found by dividing the mass by the volume (density = mass ÷ volume). This concept helps explain why some substances feel heavy for their size and why objects float or sink in a liquid: a substance with a higher density than the surrounding liquid will sink, while one with a lower density will float. For example, water has a density of about 1 g/mL, which serves as a common reference; many metals have densities well above this, so they feel very heavy for their size. Units are typically g/cm³ for solids and kg/m³ for liquids and gases. The other terms aren’t measures of mass per volume: a characteristic property identifies a substance but isn’t a measurement itself; the mean is an average of numbers; a solvent is the substance that dissolves solutes.

Mass per unit volume is called density. It tells you how much matter is packed into a given space and is found by dividing the mass by the volume (density = mass ÷ volume). This concept helps explain why some substances feel heavy for their size and why objects float or sink in a liquid: a substance with a higher density than the surrounding liquid will sink, while one with a lower density will float. For example, water has a density of about 1 g/mL, which serves as a common reference; many metals have densities well above this, so they feel very heavy for their size. Units are typically g/cm³ for solids and kg/m³ for liquids and gases. The other terms aren’t measures of mass per volume: a characteristic property identifies a substance but isn’t a measurement itself; the mean is an average of numbers; a solvent is the substance that dissolves solutes.