Question

Describe what happens to the particles in the substances

when you dissolve sodium chloride in water to make brine.

Answer 1

When you dissolve sodium chloride (NaCl) in water to make brine, the particles of NaCl separate and disperse uniformly throughout the water. This process is known as dissolution or hydration.

In a crystal of solid NaCl, the sodium (Na+) and chloride (Cl-) ions are arranged in a regular, three-dimensional lattice structure held together by strong ionic bonds. However, when NaCl is placed in water, the polar water molecules surround each ion and weaken the ionic bonds, causing the crystal lattice to break apart. The positive ends of the water molecules (hydrogen atoms) are attracted to the negative chloride ions, while the negative ends of the water molecules (oxygen atoms) are attracted to the positive sodium ions.

As the ionic bonds weaken, individual Na+ and Cl- ions are pulled away from the crystal lattice and surrounded by water molecules, forming hydrated ions. The hydrated ions are now free to move around in the water, which allows them to conduct electricity and gives brine its characteristic electrical conductivity.

Overall, the dissolution of NaCl in water results in the separation of the Na+ and Cl- ions, and their dispersion throughout the water. This process is a physical change, as the chemical identity of the Na+ and Cl- ions remains the same before and after dissolving in water

Answer 2

When you dissolve sodium chloride (NaCl) in water to make brine, the particles in both the NaCl and water interact with each other in a specific way.

Sodium chloride is an ionic compound, which means that it is made up of positively charged sodium ions (Na+) and negatively charged chloride ions (Cl-). When NaCl is added to water, the polar water molecules interact with the charged ions, separating them from each other and forming a solution.

The positive end of the water molecules (the hydrogen atoms) is attracted to the negative chloride ions, while the negative end of the water molecules (the oxygen atom) is attracted to the positive sodium ions. As a result, the water molecules surround and separate the individual ions, effectively breaking apart the crystal lattice structure of the solid NaCl.

The Na+ and Cl- ions become surrounded by water molecules, forming a type of shell or hydration sphere around each ion. This process is called hydration. The hydrated ions then become evenly distributed throughout the solution, resulting in a homogeneous mixture of NaCl and water, also known as brine.

So, in summary, when NaCl is dissolved in water, the polar water molecules interact with the ionic Na+ and Cl- ions, breaking apart the crystal lattice structure of the solid NaCl, and forming a homogeneous mixture of hydrated ions and water molecules.