At low pressure molecules of gas are far from each other due to which gas molecules have enough mean free path to accelerate. … As the ionization of molecules will occur there will be free electrons as we know that free electrons conduct electricity. And this is why gases conduct electricity at low pressure.
Why do gases do not conduct electricity?
At high pressure, the mean free path of electrons is quite small. The electrons don’t get enough time to get accelerated. If the electrons don’t accelerate for long, they can’t gain the high velocity or kinetic energy that is required to ionize other atoms. So gases can not conduct electricity at higher pressures.
Why does electric discharge takes place at low pressure and high potential difference?
Low pressure means that less number of gas molecules is present in the discharge tube. … Moreover, high voltage increases the kinetic energy of the electrons which in turn increases the probability of removal of electrons form the gaseous molecules.
Why is gas a poor conductor of heat?
Gases are very poor conductors of heat because their particles are widely separated so that collisions do not occur frequently to enable efficient energy transfer.
Why dry gas is insulator at NTP?
At NTP, gases are insulators of electricity as molecules do not have free charge particles for migration at this condition. At the high voltage and low pressure, gases act as conducting medium due to the formation of ions.
Why is conduction easier in gases if the pressure is low will the conduction continue to improve if the pressure is made as low as nearly zero?
Answer : Conduction happens when an electron with enough kinetic energy collides with the electron of gas atoms. … Whereas at low pressure due to an increase in their mean free path they are able to gain enough kinetic energy for ionization process so conduction is easier.
Why do gases have low pressure?
The pressure we measure comes from the force of the gas molecules hitting the walls of the container. Attractive forces between the molecules will pull them a little closer together, which effectively slows the molecule down a little before it hits the container wall.
Why does a gas conducts current only at low pressure and high voltage?
Low pressure ensures fewer number of particles. High voltage is required to ionize gas which is a process of taking out electrons from atom. As the electrons are strogly bound so you need sufficient energy to do so.
Why does lightning discharge occur at high altitude but not at low altitude?
Actually electric discharge takes place at low pressure because a small electric field is required. We know that at high altitude, pressure is very low with respect to low altitude for some electric field set – up in the atmosphere, the electron discharge takes place at high altitude but not at low.
Why the electrical discharge through the gases could be observed only at very low pressure and at very high voltage?
1)It can only be observed so because air is a poor conductor and on such harsh conditions(high voltage and low pressure) air conducts electricity.
Why are liquid and gases not good conductors?
Solids are good conductors of heat while liquids & gases are bad conductors. Molecules of liquids and gasestransfer heat by convection, i.e. their molecues carry the heat and move. They don’t conduct. In solids the molecules are tightly packed and hence cannot move from place to place.
Why air is not a good conductor of heat?
Air may be a bad conductor of heat because its molecules aren’t in continuous contact with one another. Air molecules are too far to disperse heat to at least one another efficiently. Heat is transferred or conducted by molecules and atoms that are very closely bonded together and vibrating at high frequency.
Why conduction of heat does not take place in gases Class 9?
Solid substances particles are very close together, whereas gas particles will actually move are far apart as possible. When the particles are farther apart it makes the transfer of energy much less efficient. That is why conduction of heat does not take place in gases.
Why low pressure is used in discharge tube?
You need the low pressure in the tube so that the passage of the beam of electrons is not impeded very much by collision with air molecules. You need a reasonably high accelerating voltage to give the electrons enough kinetic energy to make the fluorescent screen glow when the electrons hit the screen.
Do different gases taken in the discharge tube at the same pressure give electric discharge at the same potential?
If different gases are filled turn by turn at the same pressure in the discharge tube the discharge in them takes place at the same potential.
Do different gases taken in the discharge tube at the same pressure give electric discharge at the same potential explain?
Do different gases taken in the discharge tube at the same pressure give electric discharge at the same potential? … <br> Reason : The discharge depends only on the pressure of discharge tube and not on the ionisation potential of gas.