Q. 274.2( 5 Votes )
Fill in the blank
(a) The number of protons in the nucleus of an atom is called its atomic no.
(b) The total number of protons and neutrons in the nucleus of an atom is called its mass no. .
(c) An atom has atomic mass number 23 and atomic number 11. The atom has 11 Electrons.
(d) An atom of an element has 11 protons, 11 electrons and 12 neutrons. The atomic mass of the atom is 23.
(e) If the nucleus of an atom has atomic number 17, mass number 37 abd there are 17 electrons outside the nucleus, the number of neutrons in it is 20.
(f) Almost all the mass of an atom is concentrated in a small region of space called the nucleus.
(g) Cathode rays are a beam of fast moving electrons.
(h) The anode rays obtained form hydrogen gas consist of particles called protons.
(i) The maximum number of electrons that can be accommodated in L shell are 8.
(j) The maximum number of electrons that can go into the M shell is 18
(k) The subatomic particle not present in a hydrogen atom is neutron.
(l) The electron has negative. charge, the proton has positive charge, and the neutron has no charge.
Rate this question :