Why is Helium used in divers' tank but not hydrogen gas?
a) Helium is lighter than hydrogen.
b) Helium is inert to any chemical reactions.
c) Helium is cheaper.
d) Helium is easy to get from market.
a) Helium is lighter than hydrogen.
b) Helium is inert to any chemical reactions.
c) Helium is cheaper.
d) Helium is easy to get from market.
b) Helium is inert to any chemical reactions.
Stability of hydrides of group 16 elements
a) increases down the group
b) decreases down the group
c) all hydrides are equally stable
d) none of the above
The lowest boiling point of helium is due to its
a) Inertness
b) Gaseous nature
c) Weak van der Waals force between atoms
d) electronic configuration
Identify the correct order of acidic strength for H-X
a) HCl > HBr > HI.
b) HCl > HI > HBr.
c) HI > HCl > HBr.
d) HI > HBr > HCl.
On a large-scale nitric acid is prepared mainly by
a) Haber's process
b) Ostwald’s process
c) Contact Process
d) Deacon's process
Chlorine water on standing loses its yellow colour due to the formation of
a) Cl and HOCl.
b) HCl and HOCl.
c) HOCl and \(HOCl_2\).
d) HCl and \(HOCl_2\).
\(SO_2\) is ----------and \(TeO_2\) is -------- agent
a) reducing, an oxidising
b) an oxidising, reducing
c) reducing, reducing
d) an oxidising, an oxidising
Hypochlorous acid and perchloric acid are, respectively:
a) HOCl and \(HClO_4\).
b) HOCl and \(HClO_3\).
c) \(HClO_2\) and \(HClO_3\).
d) \(HClO_2\) and \(HClO_4\).
Consider the figure and mark the correct option.
(a) water will move from side (A) to side (B) if a pressure lower than osmotic pressure is applied on piston (B).
(b) water will move from side (B) to side (A) if a pressure greater than osmotic , pressure is applied on piston (B).
(c) water will move from side (B) to side (A) if a pressure equal to osmotic pressure is applied on piston (B).
(d) water will move from side (A) to side (B) if pressure equal to osmotic pressure is applied on piston (A).
The reaction R-Br + NaCN → R – CN + NaBr is an example of –
(a) Elimination Reaction.
(b) Nucleophilic Substitution.
(c) Electrophilic Substitution.
(d) Oxidation Reduction.
Which of the following aqueous solutions containing 10 g of solute in each case, has highest m.p.?
(a) NaCl solution
(b) KCl solution
(c) sugar solution
(d) glucose solution
Which of the following is an example of vic-dihalide?
(a) Dichloromethane.
(b) 1,2-dichloroethane.
(c) Ethylidene chloride.
(d) Allyl chloride.
Which statement is incorrect about peptide bond?
(a) C-N bond length in proteins is longer than usual bond length of C-N bond.
(b) Spectroscopic analysis shows planar structure of -CO-NH- group
(c) C-N bond length in proteins is smaller than usual bond length of C-N bond
(d) None of the above
When KMnO₄ solution is added to oxalic acid solution, the decolourisation is slow in the beginning but becomes instantaneous after some time because
(a) CO₂ is formed as the product.
(b) The reaction is exothermic.
(c) MnO₄⁻ catalyses the reaction.
(d) Mn²⁺ acts as an auto-catalyst.