GENERAL KNOWLEDGE

Detailed explanation-1: -The nucleus, with its four protons and five neutrons, is surrounded by a cloud of electrons. In 1911, Ernest Rutherford discovered that at the core of every atom is a nucleus. Atomic nuclei consist of electrically positive protons and electrically neutral neutrons.

Detailed explanation-2: -Tritium is an isotope of hydrogen whose nucleus Triton contains 2 neutrons and 1 proton.

Detailed explanation-3: -Like the proton and other baryon particles, the neutron consists of three quarks.

Detailed explanation-4: -The helium nucleus or α-particle, which may form a constituent of heavier nuclei, is composed of two protons and two neutrons.