The most abundant element in the universe
Aluminium
Nitrogen
Carbon
Hydrogen
H2 + S → ?
H2S
HS
2HS
H2SO4
Hydrogen is a
blue colour gas
pink colour gas
colourless
green colour gas
Which of these is not used for the preparation of hydrogen?
Na
O
K
Pb
Substance which alter the rate of chemical reaction is
oxidizing agent
catalyst
reducing agent
none of these
Which of the following reactions is /are the preparation of Hydrogen?
Reaction of Potassium with cold water
Reaction of magnesium with boiling water
Reaction of Iron with steam
All of these
Valency of hydrogen is
3
2
1
5
Which of the following is the lightest known element?
Helium
Lithium
Neon
Which property of hydrogen is used for the extraction of metals?
oxidising property
reducing property
physical property
Oxidation is the process of
addition of oxygen
removal of oxygen
addition of O3
addition of carbon