Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
A solution is a homogeneous mixture of two or more chemically non-reacting substances whose composition can be varied within certain limits.
A binary solution consists of two components: the Solvent (the component present in the largest quantity) and the Solute (the component present in a smaller quantity).
Solutions are classified into nine types based on the physical state of the solute and the solvent (Solid, Liquid, or Gas).
Gaseous Solutions: The solvent is always a gas. Examples include gas in gas (Air), liquid in gas (Chloroform mixed with nitrogen gas), and solid in gas (Camphor in nitrogen gas).
Liquid Solutions: The solvent is always a liquid. Examples include gas in liquid ( dissolved in water), liquid in liquid (Ethanol dissolved in water), and solid in liquid (Glucose dissolved in water).
Solid Solutions: The solvent is always a solid. Examples include gas in solid (Solution of hydrogen in palladium), liquid in solid (Amalgam of mercury with sodium), and solid in solid (Copper dissolved in gold).
The concentration of a solution is the amount of solute dissolved in a known amount of solvent or solution, expressed through various units like Molarity (), Molality (), and Mole Fraction ().
📐Formulae
💡Examples
Problem 1:
Identify the type of solution and the physical state of the solute and solvent in 'Amalgam of mercury with sodium'.
Solution:
Type: Liquid in Solid solution. Solute: Mercury (, liquid); Solvent: Sodium (, solid).
Explanation:
In an amalgam, mercury is the liquid component dispersed within the solid metal lattice of sodium.
Problem 2:
Calculate the mole fraction of ethylene glycol () in a solution containing of by mass.
Solution:
Mass of , Mass of water = . Moles of . Moles of water = \frac{80}{18} \approx 4.444\text{ mol}\chi_{glycol} = \frac{0.322}{0.322 + 4.444} \approx 0.068$.
Explanation:
Mole fraction is the ratio of the number of moles of a particular component to the total number of moles of all components in the solution.
Problem 3:
Give an example of a solid in gas solution.
Solution:
Camphor in nitrogen gas.
Explanation:
In this case, the solid particles of camphor (solute) are sublimated and distributed homogeneously within the nitrogen gas (solvent).