Electrons are embedded in the sphere of _____________charge.

The mass of an electron is about ______________ the mass of a hydrogen atom

The absolute mass of a proton is _____________g.

At normal pressure air or any other gas is a non - conductor of electricity, but at ____________ pressures the gases become conductors of electricity.

J.J. Thomson was the ______________  scientist to propose a model for the structure of an atom.

In Rutherford experiment, ____________ of the -particles were deflected by the foil by small angles.

Which of the following  statement / statements are correct :

(a) The absolute mass of a proton is g.

(b) The mass of a proton is 1838 times that of an electron.

Which of the following statement / statements are correct :

(a) Protons are positively charged particles and are denoted by ‘p+’

(b) Anode rays are also known as Canal rays.

(c) The anode rays are discovered by E. Goldstein.

Which of the following statement / statements are correct :

(a) J.J Thomson discovered electron.

(b) Electron are negatively charged particle and are denoted by e^-

Which of the following are the limitations of Thomson model :

(a) It could not explain the stability of the atom ,i.e. how positive and negative charges could remain, so close together.

(b) It could not explain the distribution of electrons in the extra nuclear portion of the atom.