Chemistry
Which of the following statements is not correct about the characteristics of cathode rays ?
- They start from cathode and move towards anode.
- They do not depend upon the material of the electrode.
- Their characteristics depend upon the nature of the gas present in the cathode ray tube.
- They travel in straight lines in the absence of an external electrical or magnetic fields.
Answer
Their characteristics depend upon the nature of the gas present in the cathode ray tube.
Reason - Cathode rays are independent of the gas present in the tube. Their properties remain the same in different gases.
Cathode rays are streams of electrons emitted from the cathode and attracted to the anode. Cathode rays have the same properties regardless of the electrode material. Cathode rays move in straight lines unless deflected by fields.
Related Questions
When a metal atom becomes an ion:
- It loses electrons and is oxidized.
- It gains electrons and is reduced.
- It gains electrons and is oxidized
- It loses electrons and is reduced.
An element Y has 2 electrons in the 2nd orbit and X has 7 electrons in its 3rd orbit. The compound formed between them has the formula:
- XY2
- YX2
- YX
- Y7X2
Which statement is incorrect about electrons ?
- Electron is a negatively charged particle.
- Its mass is equal to the mass of neutron.
- It is a constituent of cathode rays.
- It is a basic constituent of all atoms.
Two atoms are said to be isobars if they have the same:
- number of neutrons but different number of electrons.
- number of electrons but different number of neutrons.
- atomic number but different mass numbers.
- sum of protons and neutrons but the number of protons is different.