Question

Make it correct statements.

1. When an element accepts 2 electrons its valence shell, its valency is 2+.
2. The shell closest to the nucleus of an atom is called valence shell.
3. The formula of an oxide of aluminium is Al³0².
4. The collective name of all particles found within the nucleus is nuclear particles.
5. The symbol of the chlorine gas is CI².​

Answer 1

Answer:

1)Helium atom has only one shell (K shell) which can have maximum 2 electrons. Thus, its shell is already complete called duplet. It can neither lose electrons nor gain electrons. Hence, its valency is 'zero'.

2)The number of electrons in the outermost shell of a particular atom determines its reactivity, or tendency to form chemical bonds with other atoms. This outermost shell is known as the valence shell, and the electrons found in it are called valence electrons.

3)Al²O³

4)The nucleus of an atom consists of neutrons and protons, which in turn are the manifestation of more elementary particles, called quarks, that are held in association by the nuclear strong force in certain stable combinations of hadrons, called baryons.

5)Cl²