Helium is unreactive.
the substance in helium is h2o
Helium is pure as it is on the periodic table.
Air has many more different substances than helium, which is a single substance. Outside air contains helium.
Chemical Change.
Helium is an element which makes it a pure substance.
the substance in helium is h2o
Helium is pure as it is on the periodic table.
Air has many more different substances than helium, which is a single substance. Outside air contains helium.
Chemical Change.
chemical change
Helium gas is a pure substance
Helium gas is a pure substance
Chemical Change
Chemical change.
Chemical change.
Chemical Change.
Chemical Change.