Which one of the following regarding helium is incorrect? 

• Helium is a noble gas having low melting and boiling point. Some of the uses of helium are, it is used in nuclear reactors as coolant and used to make superconducting magnets. It is also used as cryogenic agents to carry out experiments at low temperature. 

Thus the incorrect statement is, it is used to fill gas balloons instead of hydrogen because it is lighter and non-inflammable because helium is heavier in mass.