Periodic table gaseous elements

Situated between the solid and gaseous states as the only non-metallic element liquid at ambient temperature, bromine is sandwiched in the periodic table between the ubiquitous chlorine and the rather rare iodine. In terms of production volumes it is neither a bulk commodity chemical like chlorine, nor a speciality chemical like iodine. And commercially, bromine is beset by uncertainty. Until the 1970s, the major market forbromine was in dibromoethane - a co-additive for leaded petrol. The phase-out of lead in petrol could have spelled the collapse of the bromine industry, but alternative bromine markets developed and the industry both rationalised and flourished. However, although world bromine production continues to increase slowly, fresh environmental concerns have emerged and the industry is once more under threat. Details are given. 19 refs. 

Symbol H atomic number 1 atomic weight 1.0079 the lightest of all the chemical elements the first element in the Periodic Table Group lA (group 1) nonmetallic gaseous element occurs as H2, a diatomic molecule electron configuration Ish valences -i-l and-1 three isotopes H-1 or protium (99.9844%), H-2 or deuterium (0.0156%), H-3 or tritium (radioactive, ty, =12.4 yr., in traces... 

The nonmetallic elements, with the exception of hydrogen, are on the right of the periodic table. Nonmetals are very poor conductors of electricity and heat and may also be transparent. Solid nonmetals are neither malleable nor ductile. Rather, they are brittle and shatter when hammered. At 30°C (86°F), some non-metals are solid (carbon, C), others are liquid (bromine, Br), and still others are gaseous (helium, He). 

Fig. 3. Extrapolation of the standard enthalpies of monatomic gaseous elements AH%)sM(g) along the groups of the periodic table based on the atomic number Z (Method /).

Thinking Criticaiiy A gaseous element is a poor conductor of heat and electricity, and is extremely nonreactive. Is the element likely to be a metal, nonmetal, or metalloid Where would the element be located on the periodic table Explain. 

Periodic table of the elements with the categories of conservative, bioactive, adsorbed, and gaseous elements indicated. 

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