The densities of the liquid and solid states of a substance are often similar. Explain.
Density is related to intermolecular or other inter-particle distances. These are dependent on molecular or ionic radii, intermolecular attractions (or other cohesive forces), dispersive forces (repulsions) and molecular kinetic energies (molecular speeds). All these factors are similar in solids and liquids.
a roll of aluminum has a mass of 1.08kg. what is its mass in pounds? (1 lb= 435.6g)
an easier answer is both solid and liquid particles
are held together by attractive force
The similarity in densities between the liquid and solid states of a substance can be explained by the nature of the intermolecular forces present within the substance.
In general, substances in their solid state have tightly packed and organized arrangements of particles, which is why solids have a definite shape and volume. The intermolecular forces between these particles are strong, holding them closely together. These strong forces also lead to a higher density in the solid state.
When a solid substance is heated, its particles gain energy and begin to vibrate with increased amplitude. At a certain temperature, known as the melting point, the intermolecular forces are weakened enough to allow the solid to convert into a liquid state. In the liquid state, the particles have more freedom to move, though they still have some intermolecular attractions. The distance between the particles increases, resulting in a decrease in the density compared to the solid state.
However, despite the distance between the particles increasing, the intermolecular forces in liquids are still present to some extent. These forces can cause the particles to come into close proximity, leading to a certain level of organization and packing. Consequently, the density of the liquid state may still remain relatively high, approaching the density of the solid state.
It is important to note that not all substances exhibit similar densities between their liquid and solid states. For example, water is a well-known exception, as its solid (ice) is less dense than its liquid form. This is due to the unique structure of the water molecule, which causes it to expand when it freezes, leading to a decrease in density.