The type of hardness that occurs due to the presence of bicarbonate of calcium and magnesium ions hardness is __________…

The property of hydrogen of forming diatomic molecule is from __________

Hydrogen peroxide is __________ in nature.

What is the half-life of atomic hydrogen?

Which of the following statements is true regarding the density of isotopes of the hydrogen?

At high electric discharge hydrogen and oxygen combine to form _________

Pure zinc is not used in the production of hydrogen.

Metallic hydrides are powerful _________ agents.