What is the effect of temperature on surface tension and viscosity of a liquid?

What is the effect of temperature on surface tension and viscosity of a liquid?
by

1 Answer

Answer :

Ans. Both decrease by increasing temperature.
by

Related questions

Define i) surface tension ii) viscosity. Give their units.

Description : Define i) surface tension ii) viscosity. Give their units.

Last Answer : Ans.i) The force acting parallel to the surface and perpendicular to a line of unit length anywhere in the surface is called surface tension. Its unit is Nm-1 . ii) The force of friction which one part of the liquid offers to another part of the liquid is called viscosity. Its unit is poise.

Explain the effect of increasing the temperature of a liquid, on intermolecular forces operating between its particles. What will happen to the viscosity of a liquid if its temperature is increased? Arrange the following in increasing order of viscosity-water, hexane, glycerine.

Description : Explain the effect of increasing the temperature of a liquid, on intermolecular forces operating between its particles. What will happen to the viscosity of a liquid if its temperature is increased? Arrange the following in increasing order of viscosity-water, hexane, glycerine.

Last Answer : Ans. On increasing the temperature , the kinetic energy of liquid molecules increases so that it can overcome the attractive forces between the molecules and hence liquid can flow more easily i.e. viscosity decreases. Order of increasing viscosity : hexane < water < glycerine.

Predict the entropy change in- (i) A liquid crystallizes into solid (ii) Temperature of a crystalline solid raised from 0K to 115K.

Description : Predict the entropy change in- (i) A liquid crystallizes into solid (ii) Temperature of a crystalline solid raised from 0K to 115K.

Last Answer : Ans. (i) Entropy decreases because molecules attain an ordered state. (ii) Entropy increases because from 0K to 115K average kinetic of moleculesincreases.

Write the effect of temperature on Equilibrium constant.

Description : Write the effect of temperature on Equilibrium constant.

Last Answer : Ans. The value of Equilibrium constant changes with the temperature. The increase in rate depends upon activation energy .As the activation energy are different for forward & backward direction .So temperature will ... & backward direction. As K= Kf/ Kb ,so the state of equilibrium will be altered.

Applying Le- Chatelier's principle, predict the effect of temperature and pressure on evaporation of water.

Description : Applying Le- Chatelier's principle, predict the effect of temperature and pressure on evaporation of water.

Last Answer : Ans Evaporation of water can be represented as water + heat water vapours: i) With increase in pressure- the equilibrium tend to shift in direction where there is decrease in the vol. i.e. ... left. ii) with increase in temperature- the equilibrium shifts to right as it is an endothermic reaction.

Why liquid drops are spherical in shape?

Description : Why liquid drops are spherical in shape?

Last Answer : Ans. Because of surface tension, the molecules tend to minimize the surface area and sphere has minimum surface area.

Arrange solid, liquid and gas in order of energy. Give reason.

Description : Arrange solid, liquid and gas in order of energy. Give reason.

Last Answer : Ans. Solid < liquid < gas. This is because solid absorb energy to change into a liquid which further absorb energy to change into a gas.

Name two intermolecular forces that exist between HF molecules in liquid state.

Description : Name two intermolecular forces that exist between HF molecules in liquid state.

Last Answer : Ans. Dipole-dipole interaction and hydrogen bonding.

What will be the effect on equilibrium if (i) a catalyst is added to it (ii) An inert gas is added at constant volume

Description : What will be the effect on equilibrium if (i) a catalyst is added to it (ii) An inert gas is added at constant volume

Last Answer : Ans. (i) The state of equilibrium is not disturbed on adding catalyst rather it is attained quickly. (ii) No effect on state of equilibrium

What would have the effect on the gas pressure if collisions between the gas molecules are not elastic?

Description : What would have the effect on the gas pressure if collisions between the gas molecules are not elastic?

Last Answer : Ans. The gas pressure would gradually become zero as molecules will gradually slow down and ultimately settle down due to constant loss of energy.

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

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

Last 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 ... . And if these forces are weak then the m.p and b.p will be relatively lower.

What is effect of heating on solids?

Description : What is effect of heating on solids?

Last Answer : On heating the solids, the vibrational energy of solid molecules or atoms increases, due to which vibrational motion of solid particles increases, as a result cohesive forces between the solid particles ... start melting, and convert into liquids. This temperature is called melting point of a solid.

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

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

Last Answer : Ans. No effect.

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.

Two ideal gases under same pressure and temperature are allowed to mix in an isolated system. What will be the sign of entropy change?

Description : Two ideal gases under same pressure and temperature are allowed to mix in an isolated system. What will be the sign of entropy change?

Last Answer : Ans. Entropy change (∆S) is positive. It is because disorder or degree of freedom increases on mixing.

Classify the following properties as extensive and intensive properties: Molar heat capacity, temperature, enthalpy and volume.

Description : Classify the following properties as extensive and intensive properties: Molar heat capacity, temperature, enthalpy and volume.

Last Answer : Ans. Extensive properties : Enthalpy and volume. Intensive properties: Molar heat capacity, temperature.

i)Vapour pressure increases with increase in temperature. ii)Giycerine is more viscous than water.

Description : i)Vapour pressure increases with increase in temperature. ii)Giycerine is more viscous than water.

Last Answer : Ans. i) At higher temperature inter particle attraction weakens and more number of mole cules escape to vapour. ii) As interparticle forces are stronger in glycerine.

Which of the following is the most controlling factor for the rate of bubble detachment from the hot solid surface? (A) Liquid density (B) Liquid viscosity (C) Hot surface temperature (D) Interfacial tension

Description : Which of the following is the most controlling factor for the rate of bubble detachment from the hot solid surface? (A) Liquid density (B) Liquid viscosity (C) Hot surface temperature (D) Interfacial tension

Last Answer : (D) Interfacial tension

Which of the following is the term used for the resistance of a liquid system to flow? w) surface tension x) diffusion y) viscosity

Description : Which of the following is the term used for the resistance of a liquid system to flow? w) surface tension x) diffusion y) viscosity

Last Answer : ANSWER: Y -- VISCOSITY

Why is the PH of blood remains almost constant?

Description : Why is the PH of blood remains almost constant?

Last Answer : Ans: Blood is a buffer solution and resist the change in PH

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?

Description : What is the molarity of pure water?

Last Answer : Ans: 55.5M

What type of substances are generally called 'electrolyte'?

Description : What type of substances are generally called 'electrolyte'?

Last Answer : Ans: Acid, bases and salts

Why the Equilibrium constant is taken as dimensionless?

Description : Why the Equilibrium constant is taken as dimensionless?

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?

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

Last Answer : Ans. In soda water bottle carbon dioxide gas is dissolved under pressure. As soon as the bottle is opened, the pressure inside the bottle tends to decrease, so the solubility decreases and gas escapes out.

Write the significance of equilibrium constant?

Description : Write the significance of equilibrium constant?

Last Answer : Ans.The numerical value of equilibrium constant is a measure of the extent to which the reactants have been converted into products. A large value of K indicates large amount of ... its low value indicates less amount of reactants converted into products before achieving the equilibrium state.

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

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

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

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

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

Last Answer : Ans. Kc=1/4

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

Write Application of Equilibrium constant?

Description : Write Application of Equilibrium constant?

Last Answer : Ans. (i) To predict the extent of the reaction. (ii) To predict the direction of the reaction. (iii) To calculate the equilibrium concentration.

Write characteristics of Chemical equilibrium.

Description : Write characteristics of Chemical equilibrium.

Last Answer : Ans. (i) At equilibrium the rate of forward reaction becomes equal to rate of backward reaction. (ii) A chemical equilibrium established only if none of the products are allowed to escape out ... can be attained from either direction. (iv) Catalyst does not alter the state of equilibrium.

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

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.

Is the bond energy of all the four C-H bonds in CH4 molecule equal? If not then why ? How is C-H bond energy then reported?

Description : Is the bond energy of all the four C-H bonds in CH4 molecule equal? If not then why ? How is C-H bond energy then reported?

Last Answer : Ans. No because after breaking of C-H bonds one by one, the electronic environments change. The reported value is the average of of the bond dissociation energies of the four C-H bonds.

What is the value of ∆G where ice and water are in equilibrium?

Description : What is the value of ∆G where ice and water are in equilibrium?

Last Answer : Ans. ∆G=0

What is the sign of enthalpy of formation of highly stable compound?

Description : What is the sign of enthalpy of formation of highly stable compound?

Last Answer : Ans. Negative.

Which have more entropy real crystal or ideal crystal and why?

Description : Which have more entropy real crystal or ideal crystal and why?

Last Answer : Ans. Real crystal has more entropy because it has more disorderness.

Out of carbon(diamond)and carbon (graphite) whose enthalpy of formation is taken as zero?

Description : Out of carbon(diamond)and carbon (graphite) whose enthalpy of formation is taken as zero?

Last Answer : Ans. Enthalpy of formation of carbon in the form of graphite is taken as zero because it is a more commonly found in stable form of carbon.

Predict the sign of ∆S for (a) the process of evaporation (b) the process of freezing.

Description : Predict the sign of ∆S for (a) the process of evaporation (b) the process of freezing.

Last Answer : Ans. (a) ∆S =+ve (b) ∆S=-ve

When ΔH>0 and ΔS< 0, reaction is never spontaneous. Explain.

Description : When ΔH>0 and ΔS< 0, reaction is never spontaneous. Explain.

Last Answer : Ans. When ΔH > 0 , energy factor opposes the reaction . When ΔS< 0, i.e. randomness decreases, this factor also opposes the process. As both factors oppose the process, reaction is never spontaneous.

Under what condition, the heat evolved or absorbed in a reaction is equal to its free energy change?

Description : Under what condition, the heat evolved or absorbed in a reaction is equal to its free energy change?

Last Answer : Ans. As ΔG = ΔH – TΔS. Thus, ΔG = ΔH only when either the reaction is carried out at 0^0 K or the reaction is not accompanied by any entropy change, i.e., ΔS = 0

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

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

Last Answer : Ans. C(s) +1/2 O2(g) → CO (g)

What is meant by entropy driven reaction? How can the reaction with positive change of enthalpy and entropy be made entropy driven?

Description : What is meant by entropy driven reaction? How can the reaction with positive change of enthalpy and entropy be made entropy driven?

Last Answer : Ans.The free energy change of a reaction is given by ΔG = ΔH - TΔS For a reaction to be spontaneous, ΔG should be -ve. If both ΔH and ΔS are positive ΔG can be -ve if TΔS>ΔH in magnitude. Thus, entropy ... is low, TΔS should be greater than ΔH (ii) If ΔS is small, T should be so large that TΔS>ΔH.

Under what condition, the heat evolved/absorbed in a reaction is equal to its free energy change?

Description : Under what condition, the heat evolved/absorbed in a reaction is equal to its free energy change?

Last Answer : Ans. In ∆G = ∆H – T. ∆S, when reaction is carried out at 0 K or ∆S = 0, then ∆G = ∆H.

A real crystal has more entropy than an Ideal crystal. Why?

Description : A real crystal has more entropy than an Ideal crystal. Why?

Last Answer : Ans. A real crystal has some disorder due to presence of defects in their structural arrangement, and Ideal crystal does not have any disorder.

What is spontaneous change? Give one example.

Description : What is spontaneous change? Give one example.

Last Answer : Ans. A process which can take place of its own or upon initiation under some condition. eg. Common salt dissolves in water of its own.

From thermodynamic point to which system the animals and plants belong?

Description : From thermodynamic point to which system the animals and plants belong?

Last Answer : Ans. Open system.