Noble gases (18): (name all noble gases) • these elements do not easily combine with other elements. they are odorless, colorless and therefore were difficult to discover. • when air is cold, oxygen liquefies first at -18o celsius. about 1% of the air is still gas composed of the noble gas entire noble gas short version of noble gas • one noble gas was discovered on the sun. it’s spectrum was identify first. this is • one of noble gas is radioactive and seeps up your basement floors and walls. it is • this noble gas is used in electronic flashes and other bright lights. it is• this noble gas is best known for its orange color in gas discharge tubes. it is used for signs that bear its name. it is