$3 \mathrm{g}$ of a solute is dissolved in $30 \mathrm{g}$ of water to form a saturated solution at $298 \mathrm{K}$. Calculate the solubility of the solute at this temperature.

Three mixtures $\mathrm{A}, \mathrm{B}$ and $\mathrm{C}$ are obtained by stirring three different solids in water taken in separate beakers. When mixture $\mathrm{A}$ is allowed to stand for some time, then its particles settle at the bottom of the beaker. When a beam of light is passed through mixture $\mathrm{A}$ in a dark room, the path of light becomes visible when observed from the side of the beaker. When mixture $\mathrm{B}$ is allowed to stand for a considerable time, even then its particles do not settle down. Mixture $\mathrm{B}$, however, scatters the beam of light just like mixture $\mathrm{A}$. The particles of mixture $\mathrm{C}$ do not settle down on keeping and it also does not scatter a beam of light passing through it.

What are the mixtures like $\mathrm{A}$ known as?

What are the mixtures like $\mathrm{B}$ known as?

What are the mixtures like $\mathrm{C}$ known as ?

Three mixtures $\mathrm{A}, \mathrm{B}$ and $\mathrm{C}$ are obtained by stirring three different solids in water taken in separate beakers. When mixture $\mathrm{A}$ is allowed to stand for some time, then its particles settle at the bottom of the beaker. When a beam of light is passed through mixture $\mathrm{A}$ in a dark room, the path of light becomes visible when observed from the side of the beaker. When mixture $\mathrm{B}$ is allowed to stand for a considerable time, even then its particles do not settle down. Mixture $\mathrm{B}$, however, scatters the beam of light just like mixture $\mathrm{A}$. The particles of mixture $\mathrm{C}$ do not settle down on keeping and it also does not scatter a beam of light passing through it.

Name the phenomenon exhibited by $\mathrm{A}$ and $\mathrm{B}$ which occurs on passing a beam of light through them.

Name one mixture each which is like $\left(\mathrm{i}\right) \mathrm{A} \left(\mathrm{ii}\right) \mathrm{B}$, and $\left(\mathrm{iii}\right) \mathrm{C}$.

When the solid $\mathrm{A}$ is added to water, it dissolves with the evolution of a lot of heat and making little explosions to form two products $\mathrm{B}$ and $\mathrm{C}$. The properties of products $\mathrm{B}$ and $\mathrm{C}$ are entirely different from those of solid $\mathrm{A}$ as well as water. Moreover, products $\mathrm{B}$ and $\mathrm{C}$ cannot be reconverted into solid $\mathrm{A}$ and water. When another solid $\mathrm{D}$ is added to water, it dissolves with the absorption of a little heat to form a product $\mathrm{E}$ which cools down. The product $\mathrm{E}$ shows the properties of both, solid $\mathrm{D}$ as well as water. Moreover, product $\mathrm{E}$ can be converted into solid $\mathrm{D}$ and water.

What type of change occurs when solid $\mathrm{A}$ is dissolved in water? Why?