Estimate the average thermal energy of a helium atom at the temperature on the surface of the Sun (6000 K)

Estimate the average thermal energy of a helium atom at room temperature (27 ^@C)

Estimate the average thermal energy of a helium atom the temperature of 10 million kelvin (the typical core temperature in the case of a star)

Estimate the average mass density of a sodium atom assuming its size to be about 2.5 overset@A . (Use the known values of Avogadro’s number and the atomic mass of sodium). Compare it with the density of sodium in its crystalline phase : 970 kg m^-3 . Are the two densities of the same order of magnitude ? If so, why ?

Estimate the fraction of electrons,which are excited from the energy gap of 1.1 eV at a temperature of 300 K. Given Boltzmann's constant, k=1.38 xx 10^(-23) J .

Arrhenius studies the effect of temperature on the rate of a reaction and postulated that rate constant varies with temperature exponentially as k=Ae^(-E_(a)//RT) . This method is generally used for finding the activation energy of a reaction. Keeping temperature constant, the effect of catalyst on the activation energy has also been studied. If x is the fraction of molecules having energy greater than E_(a) it will be given by : a) x=-(E_(a))/(RT) b) In x=-(E_(a))/(RT) c) x=e^(E_(a)//RT) d) Any of these

Arrhenius studies the effect of temperature on the rate of a reaction and postulted that rate constant varies with temperature exponentially as k=Ae^(E_(a)//RT) . Thuis method is generally used for finding the activation energy of a reaction. Keeping temperature constant, the effect of catalyst on the activation energy has also been studied. If the rate of reaction doubles for 10^(@)C rise of temperature form 290K to 300K, the activation energy of the reaction will be approximately: a) 40 Kcal mol^(-1) b) 12 Kcal mol^(-1) c) 60 Kcal mol^(-1) d) 70 Kcal mol^(-1)

Arrhenius studies the effect of temperature on the rate of a reaction and postulted that rate constant varies with temperature exponentially as k=Ae^(E_(a)//RT) . Thuis method is generally used for finding the activation energy of a reaction. Keeping temperature constant, the effect of catalyst on the activation energy has also been studied. The pre-exponetial factor in the Arrhenius equation of a first order reaction has the unit : a) mol L^(-1)s^(-1) b) L mol^(1)s^(-1) c) s^(-1) d) dimensionless

On what factors does the average kinetic energy of gas molecules depend : Nature of the gas, temperature, volume?

In a hydrogen atom, the electron and proton are bound at a distance of about 0.53 A. (a) Estimate the potential energy of the system in eV, taking the zero of the potential energy at infinite separation of the electron from proton. (b) What is the minimum work required to free the electron, given that its kinetic energy in the orbit is half the magnitude of potential energy obtained in (a)?