The nucleus of hydrogen atom is known as:

The electron distribution in an aluminum atom is:

According to Bohr-Bury scheme, the maximum number of electrons which can be accommodated in a given shell is given by the formula:

Which of the following statements about Rutherford’s model of atom are correct?

(i) Considered the nucleus as positively charged.

(ii) Established that the - particles are four times as heavy as a hydrogen atom

(iii) Can be compared to solar system

(iv) Was in agreement with Thomson’s model

Which of the following are true for an element?

(i) Atomic number = number of protons + number of electrons

(ii) Mass number = number of protons + number of neutrons

(iii) Atomic mass = number of protons = number of neutrons

(iv) Atomic number = number of protons = number of electrons