Define intermolecular forces. Also write down effect of intermolecular forces on melting points & boiling points of substances?

Define intermolecular forces. Also write down effect of intermolecular forces on melting points & boiling points of substances?
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1 Answer

Answer :

“The forces of attraction present between the molecules of a compound are called Intermolecular forces’’.

Effect of intermolecular forces on the m.p and b.p of substances
If intermolecular forces of attractions in molecules of a compound are strong then m.p & b.p of those compounds will be high.
And if these forces are weak then the m.p and b.p will be relatively lower.
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Related questions

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Based on the intermolecular forces involved, which of the following molecules will have the lowest boiling point? w) ethane x) methyl alcohol y) methyl amine z) methyl fluoride

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Most covalent compounds (a) Behave like electrolytes in the molten state (b) Have high melting and boiling points (c) Are hard substances because of strong covalent bonds (d) Are more soluble in non-polar solvents than in polar solvents

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Last Answer : Ans:(c)

Write the significance of equilibrium constant?

Description : Write the significance of equilibrium constant?

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Write Application of Equilibrium constant?

Description : Write Application of Equilibrium constant?

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Write an expression in the form of chemical equation for the standard enthalpy of formation (∆Hf) of CO (g).

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Write various means to easily liquify the gases.

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Why fragrance of perfume spread in all the room when it is opened in one corner of the room? Write name of this phenomena.

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Why is the PH of blood remains almost constant?

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How much is the percentage ionization of an electrolyte to classified is as 'weak electrolyte'?

Description : How much is the percentage ionization of an electrolyte to classified is as 'weak electrolyte'?

Last Answer : Ans:

What is the molarity of pure water?

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Last Answer : Ans: 55.5M

Why the Equilibrium constant is taken as dimensionless?

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Last Answer : Ans. Activities are used in place of molar Conc. These represent the concentration or pressure with respect to standard state.

Explain why the gas fizzes out when soda water bottle is opened?

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What are the conditions for getting maximum yield of NH3 by Haber’s process?

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Last Answer : Ans. High conc. Of N2 &H2, Low Temp. & High Pressure.

What happens to the dissociation of PCl5 in a closed vessel if He gas is introduced into it at the same temperature?

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Last Answer : Ans. No effect.

if the equilibrium constant for the reaction is 4.0, what will be the equilibrium constant for the reverse reaction.

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Which measurable property become constant in Water Water vapors equilibrium at constant temperature

Description : Which measurable property become constant in Water Water vapors equilibrium at constant temperature

Last Answer : Ans. Vapour pressure.

what do you mean by homogenous and heterogeneous equilibrium?

Description : what do you mean by homogenous and heterogeneous equilibrium?

Last Answer : Ans. Homogenous;-It is that equilibrium reaction in which all the reactants and the products are in the same phase. Heterogeneous equilibrium: - It is that equilibrium reaction in which all the reactants and the products are in two or more phases

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Description : What will be the value of K ,If reaction is reversed?

Last Answer : Ans. The value of K will get inversed.

what is Equilibrium?

Description : what is Equilibrium?

Last Answer : Ans : Equilibrium represents the state of process in which properties such as temperature, pressure ,concentration of the system do not show any change with the passage of time. OR The state in which rate of forward reaction becomes equal to the rate of backward reaction.

Explain Hess’s law.

Description : Explain Hess’s law.

Last Answer : Ans. It states that the enthalpy change of the reaction remains the same whether the reaction is carried out in one step or several steps, i.e., ∆H = ∆H1 + ∆H2 + ∆H3 +…………

We are consuming a lot of electrical energy, solar energy etc Do you, therefore, conclude that energy of the universe is continuously decreasing? Explain. Which other thermodynamic quantity is continuously increasing or decreasing?

Description : We are consuming a lot of electrical energy, solar energy etc Do you, therefore, conclude that energy of the universe is continuously decreasing? Explain. Which other thermodynamic quantity is continuously increasing or decreasing?

Last Answer : Ans. No, energy of the universe remains constant (law of conservation of energy). Entropy of the universe is continuously increasing.

Water can be lifted into the water tanks at the top of the house with the help of a pump. Then why is not considered to be spontaneous?

Description : Water can be lifted into the water tanks at the top of the house with the help of a pump. Then why is not considered to be spontaneous?

Last Answer : Ans. A spontaneous process should continue taking place by itself after initiation . But this is not so in the given case because water will go up so long as the pump is working.