CBSE
Number of hydrogen-bonded water molecules associated in CuSO4.5H2O is
one
two
three
All the five
Which of the following is not correct regarding the elecolytic preparation of H2O2?
Lead is used as cathode
50% H2SO4 is used
Hydrogen is liberated at anode
Sulphuric acid undergoes oxidation
Moist hydrogen peroxide can not be dried over conc. H2SO4 because
it can catch fire
it is reduced by H2SO4
it is oxidised by H2SO4
it is decomposed by H2SO4
Excess fluoride (over 10 ppm) in drinking water can cause
harmful effect of bones and teeth
methemoglobinemia
kidney damage
laxative effect
Hydrogen molecule differs from chlorine molecule in the following respect.
Hydrogen molecule is non-polar but chlorine molecule is polar
Hydrogen molecule is polar while chlorine molecule is non-polar
Hydrogen molecule can form intermolecular hydrogen bonds but chlorine molecule does not
Hydrogen molecule cannot participate in coordinate bond formation but chlorine molecule can
CaC2 and H2O react to produce
CH4
C2H4
C2H2
C2H6
500 mL of a sample of water required 19.6 mg of K2Cr2O7 for the oxidation of dissolved organic matter in it in the presence of H2SO4. The COD of water sample is
3.2 ppm
7.2 ppm
6.4 ppm
4.6 ppm
What are the values of n1 and n2 respectively for line in the Lyman series of hydrogen atomic spectrum 44 ?
3 and 5
2 and 3
1 and 3
2 and 4
Glauber's salt is
Na2SO4.10H2O
Na2S2O3.5H2O
CuSO4.5H2O
Na2B4O7.10H2O
Which of the following undergoes reduction with hydrogen peroxide in alkaline medium?
Mn2+
I2
PbS
Fe2+