MODEL OBJECTIVE QUESTIONS

  1. What are solutions, solute and solvents?

Ans: A homogeneous mixture of two or more substances is called solution. The dissolved substance is called solutes. The substance which dissolves a solute is called solvent.

  1. Differentiate between saturate and supersaturated solutions.
    Ans:
    A solution in which more solutes cannot be dissolved is called saturated solution. A saturated solution that can dissolve moth ,solute when the temperature is increased is called supersaturated solution.
  2. Give two properties of solutions.

Ans: The particles of solutes are present in the form of molecules or ions. There is a uniform distribution of solutes particles in the solvent.

  1. What are electrolytes and electrolysis?

Ans:     The substances that conduct electric current in aqueous solution

are called electrolytes. The process of decomposition of electrolytes into its ions is called electrolysis.

  1. What are molarity and molar solution?

Ans: The number of moles of a solute per liter of a solution is called molarity. One mole. of any substance is equal to its molecular weight. A gram molecular weight of a substance is dissolved in water to make exactly one liter of solution at 20°C. It calleda molar solution (M).

  1. What is meant by molality?

Ans: The number of moles of a substance dissolved in in 1000 cm) of solution is called molality. Gram molecular Vveight of a substance is dissolsed in 1000 cc of water. It produces molal solution.

  1. Differentiate between acid and base.

Ans:      An acid is a substance that releases hydrogen ions at when

dissok ed in water. A substance that releases hydroxyl ions (Oft) when dissolved in v.ziter is called base.

  1. What is 01? What is its relation with 11 and OH ions?

Ans:      The negative log ( a nt ilog) of hydrogen ion concentration is

called pH. Hydrogen and hydroxin I ions affect the chemical reactions in the cells. The higher the concentration of hydrogen ions (II ). the more acidic the solution. The higher the

concentration of hydroxyl (OH-) ions, the.more basic (alkaline) the solution.

  1. What is buffer? Give one example.

Ans: The substance which resists change in pH is called buffer. Its example is sodium bicarbonate.

  1. What are acidosis and alkalosis?

Ans:    An increase in ‘acidity causes acidosis. The decrease in acidity

causes alkalosis.

  1. What are the uses of buffer in bacterial culture?

Ans:      Bacteria are grown in culture medium in microbiological labs.


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Bacteria produce acids during reproduction. It changes the pH of the medium. The buffers are added to these media. It stablizes the pH.

  1. What are colloidal solution and colloidal systems?

Ans:    A heterogeneous mixture in which solute particles are larger than

molecules or ions but cannot he seen by naked eye is called colloidal solution. A system which shows propterties of colloidal solution is called colloidal system.

  1. What are dispersed and dispersion medium in colloidal
    solution?

Ans: The solvent is called the dispersion medium in a colloidal solution. The solid solute particles are called dispersed medium in colloidal solution.

  1. Differentiate between sol and gel.

Ans:    A system composed of non-viscous colloidal solution is called

sol.:For example milk. A system composed of viscous colloidal solution is called gel. For example butter.

  1. Differentiate between Lyophilic Systems and Lyophobic
    Systems.

Ans:     The system in . which dispersed phase and liquid dispersion
medium attract each .other is called lyophlic systems. The systems in which the dispersed phase and liquid dispersion phase repel each other is called lyophobic systems.

  1. What is adsorption? Give its relation with colloidal solution.

Ans: The tendency of molecules and ions to adhere to the surface of certain solids or liquids is called adsorption. Colloidal particles show a high tendency of adsorption. Thus, colloidal systems

  1. What is Tyndall cone?

Ans:      colloidal particles scatter light. This is called Tyndall effect. The

path of light appears as a cone. It is known as Tyndall cone. This property helps to detect the presence of colloidal particles.

  1. What is role of colloidal solution in Cyclosis and amboeid
    movements?

Ans: The cyclosis occurs due to phase reversal of colloidal propty. The cyclosis usually occurs in sol phase. Amoeboid movements in amoeba occur due to colloidal properties.

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