7. Chlorine product sheet

7.1 Physico-chemical properties

Under normal conditions of temperature and pressure, chlorine is a greenish-yellow gas with an irritating, toxic odor. With atomic number Z = 17, it occupies the square next to argon in the periodic table, where it is second only to fluorine among the halogens.

It was demonstrated in 1774 by C.W. Scheele when studying the attack of pyrolusite (MnO ₂ ) by hydrochloric acid.

The molar mass of chlorine is 35.453. Its enthalpy of dissociation is 239.44 kJ/mol.

The thermodynamic data for chlorine are as follows:

• enthalpy of fusion: 90.33 kJ · kg ^-1 ...