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The constancy of e/m ratio for electrons...

The constancy of `e/m` ratio for electrons insdpite of variation of gas present in the discharge tube or of the matrial of the cathode shows that

A

Electrons are negatively charged

B

Electron are universal constituents of matter

C

Electrons are the lightest of all particle

D

Mass of the electron is `1/1838` of the mass H-atom

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The correct Answer is:
b
The constancy of `e/m` ratio for electrons inspite of variation of gas present in the discharge tube or the material of the cathode shows that electrons are universal constituents of matters.
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The constancy of e/m ratio for electron shows that

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Figure 6.20 shows a metal rod PQ resting on the smooth rails AB and positioned between the poles of a permanent magnet. The rails, the rod, and the magnetic field are in three mutual perpendicular directions. A galvanometer G connects the rails through a switch K. Length of the rod = 15 cm, B = 0.50 T, resistance of the closed loop containing the rod = 9.0 m Omega . Assume the field to be uniform. (a) Suppose K is open and the rod is moved with a speed of 12 cm s^(-1) in the direction shown. Give the polarity and magnitude of the induced emf. (b) Is there an excess charge built up at the ends of the rods when K is open? What if K is closed? (c) With K open and the rod moving uniformly, there is no net force on the electrons in the rod PQ even though they do experience magnetic force due to the motion of the rod. Explain. (d) What is the retarding force on the rod when K is closed? (e) How much power is required (by an external agent) to keep the rod moving at the same speed (=12 cm s^(-1) ) when K is closed? How much power is required when K is open? (f ) How much power is dissipated as heat in the closed circuit? What is the source of this power? (g) What is the induced emf in the moving rod if the magnetic field is parallel to the rails instead of being perpendicular?

Electrolysis is the process in which electrical energy is converted to chemical energy. In electrolyte cell, oxidation takes place at anode and reduction at cathode. Electrode process depends on the electrode taken for electrolysis. Amount of substance liberated at an electrode is directly proportionation to the amount of charge passed through it. The mass of substance liberated at electrode is calculate using the following realation : m=(itE)/(96500) Here, E represent the equivalent mass and 96500 C is called the faraday constant. Faraday (96500 C) is the charge of 1 mole electron i.e., 6.023 xx 10^(23) electrons, it is used to liberate on gram equivalent of the substance. The passage of current liberates H_2 at cathode and Cl_2 at anode. The solution is

Electrolysis is the process in which electrical energy is converted to chemical energy. In electrolyte cell, oxidation takes place at anode and reduction at cathode. Electrode process depends on the electrode taken for electrolysis. Amount of substance liberated at an electrode is directly proportionation to the amount of charge passed through it. The mass of substance liberated at electrode is calculate using the following realation : m=(itE)/(96500) Here, E represent the equivalent mass and 96500 C is called the faraday constant. Faraday (96500 C) is the charge of 1 mole electron i.e., 6.023 xx 10^(23) electrons, it is used to liberate on gram equivalent of the substance. The platinum electrodes were immersed in a solution of cupric sulphate (CuSO_4) and electric current is passed through the solution. After sometimes, it was observed that the colour of copper sulphate disappeared with evolution of a gas at the electrode. The colourless solution contains.

Electrolysis is the process in which electrical energy is converted to chemical energy. In electrolyte cell, oxidation takes place at anode and reduction at cathode. Electrode process depends on the electrode taken for electrolysis. Amount of substance liberated at an electrode is directly proportionation to the amount of charge passed through it. The mass of substance liberated at electrode is calculate using the following realation : m=(itE)/(96500) Here, E represent the equivalent mass and 96500 C is called the faraday constant. Faraday (96500 C) is the charge of 1 mole electron i.e., 6.023 xx 10^(23) electrons, it is used to liberate on gram equivalent of the substance. Calculate the volume of gas liberated at the anode at STP during the electrolysis of a CuSO_4 solution by a current of 1 A passed for 16 minutes and 5 seconds.

The instantaneous rate of an elementary chamical reactkon aA+bBhArr cC+dD can be given by rate =K_(f)[A]^(a)[B]^(b)-K_(b)[C]^(c)[D]^(d) where K_(f) and K_(b) are rate constants for forward and backward reactions respectively for the reversible reaction. If the reaction is an irreversible one, the rate is expressed as, rate =K[A]^(a)[B]^(b) where K is rate contant for the given irreversible rate of disappearance of A is a/b times the rate of disappearance of B. The variation of rate constant K with temperature is expressed in terms of Arrhenius equation: K=Ae^(-E_(a)//RT) whereas the ratio (K_(f))/(K_(b)) is expressed in terms of van't Hoff isochore: (K_(f))/(K_(b))=Ae^(-DeltaH//RT) , where E_(a) and DeltaH are energy of activation and heat of reaction respectively. For an elementary reaction aAto product, the graph plotted log([-d[A]])/(dt) vs log[A]_(t) gives a straight line with intercept equal to 0.6 and showing an angle of 45^(@) then

The instantaneous rate of an elementary chamical reactkon aA+bBhArr cC+dD can be given by rate =K_(f)[A]^(a)[B]^(b)-K_(b)[C]^(c)[D]^(d) where K_(f) and K_(b) are rate constants for forward and backward reactions respectively for the reversible reaction. If the reaction is an irreversible one, the rate is expressed as, rate =K[A]^(a)[B]^(b) where K is rate contant for the given irreversible rate of disappearance of A is a/b times the rate of disappearance of B. The variation of rate constant K with temperature is expressed in terms of Arrhenius equation: K=Ae^(-E_(a)//RT) whereas the ratio (K_(f))/(K_(b)) is expressed in terms of van't Hoff isochore: (K_(f))/(K_(b))=Ae^(-DeltaH//RT) , where E_(a) and DeltaH are energy of activation and heat of reaction respectively. The variation of rate constant K and (K_(f))/(K_(b)) with temperature shows the following effects: For endothrmic reaction when T increases then K increases and (K_(f))/(K_(b)) also increases. (ii) For endothemic reaction when T decreases then K decreases and (K_(f))/(K_(b)) also decreases. (iii) For exothermic when T increases then K and (K_(f))/(K_(b)) both increases. (iv) For exothermic reaction when T decreases then K increases and (K_(f))/(K_(b)) decrease. (v) For exothermic reaction when T increases thenK and (K_(f))/(K_(b)) both decrease.

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