Which of the following best explains why the density of a substance increases due to weight concentration?

• A. Increasing the mass of a substance in a fixed volume raises its density.
• B. Density is independent of both mass and volume.
• C. Decreasing the mass of a substance in a fixed volume raises its density.
• D. Increasing the volume of a substance while keeping mass constant raises its density.

Answer: (A)

Verified step by step guidance

1. Recall the definition of density, which is the mass of a substance divided by its volume. Mathematically, density is expressed as \(\rho = \frac{m}{V}\), where \(\rho\) is density, \(m\) is mass, and \(V\) is volume.
2. Understand that if the volume is held constant, any change in mass will directly affect the density. Specifically, increasing the mass while keeping the volume fixed will increase the density because you are putting more mass into the same space.
3. Analyze the options given: the correct explanation should reflect that increasing mass in a fixed volume increases density, while decreasing mass or increasing volume (with constant mass) would decrease density.
4. Recognize that the statement 'Density is independent of both mass and volume' is incorrect because density depends on the ratio of mass to volume.
5. Conclude that the best explanation is 'Increasing the mass of a substance in a fixed volume raises its density' because it aligns with the fundamental relationship between mass, volume, and density.