Attempted
Correct
UnAttempted
Wrong
The process used for the removal of hardness of water is
Calgon process is used to remove permanent hardness of water
D2O is used in
D2O is used in nuclear reactors as moderator.
The H–O–H angle in water molecule is about
The hybridisation in water is sp3 and bond angle 104.5º
Pure water can be obtained from sea water by
Sea water is purified by reverse osmosis.
Consider the following statements :
1.Atomic hydrogen is obtained by passing hydrogen through an electric arc.
2.Hydrogen gas will not reduce heated aluminium oxide.
3.Finely divided palladium adsorbs large volume of hydrogen gas
4.Pure nascent hydrogen is best obtained by reacting Na with C2H5OH Which of the above statements is/are correct ?
Pure hydrogen is evolved by reacting absolute alcohol and Na
C2H5OH+Na→C2H5ONa+½H2
other statements are correct. See text.
Which of the following groups of ions makes the water hard?
Temporary hardness is due to presence of bicarbonates of calcium and magnesium and permanent hardness is due to the sulphates and chlorides of both of calcium and magnesium.
Calgon used as a water softener is
The complex salt of metaphosphoric acid sodium hexametaphosphate (NaPO3)6, is known as calgon. It is represented as Na2[Na4(PO3)6]
The reagent commonly used to determine hardness of water titrimetrically is
it forms calcium and magnesium complex with Ca2+ and Mg2+ ions present in hard water.
Water is :
Polarity of bond depends on difference in electronegativity of the two concerned atoms. H2O is more polar than H2S because oxygen (in O–H)is more electronegative than sulphur (in S–H).
Which of the following terms is not correct for hydrogen ?
Heavy water is stable.