Bleaching powder is obtained by the action of chlorine gas and 
Cl2 gas reacts with drys laked lime, Ca (OH)2 at 40°C to give bleaching powder
Hypo is used in photography to 
Undecomposed AgBr forms a soluble complex with hypo
It is washed with water and the image is fixed
Which of the following is a nitric acid anhydride?
Oxygen will directly react with each of th e following elements except 
(burns with blue light)
(burns with yellow light)
Chlorine does not react directly with oxygen.
Bleaching powder reacts with a few drops of dilute HCl to give 
Of the following hybrides which one h as the lowest boiling point ? 
NH3 undergoes H-bonding and hence has the highest b.p. Among the remaining hydrides i.e. PH3, AsH3 and SbH3 the b.p. increases as the size of the element increases and hence the magnitude of the van der Waal’s forces of attraction increases. Thus, PH3 has the lowest b.p.
Which of the following metal evolves hydrogen on reacting with cold dilute HNO3 ? 
Magnesium and manganese are the metals that produce hydrogen with dilute nitric acid
Which one of the following compounds does not exist ?
As Nitrogen does not have d-orbital in its valence shell its maximum covalency is 3 while in the case of other elements the maximum covalency is 5.
Each of the following is true about white and red phosphorus except that they 
Both white and red phosphorus are not soluble in CS2 only white P is soluble.
When orthophosphoric acid is heated to 600°C, the product formed is 
Which one has the lowest boiling point ?
Due to the absence of H-bonding, PH3 has the lowest b.p. The boiling point of the Vth group hydrides is : BiH3 > SbH3 > NH3 > AsH3 > PH3
The gases respectively absor bed by alkaline pyrogallol and oil of cinnamon are 
Alkaline pyrogallol absorbs O2 and oil of cinnamon absorbs O3.
It is possible to obtain oxygen from air by fractional distillation because 
Air is liquified by making use of the jouleThomson effect (cooling by expansion of the gas). Water vapour and CO2 are removed by solidification. The remaining constituents of liquid air i.e., liquid oxygen and liquid nitrogen are separated by means of fractional distillation (b.p. of O2 = –183°C : b. P. of N2 = – 195.8°C).
Which of the following statements is not correct for nitrogen ? 
In case of nitrogen, d-orbitals are not available.
The bleaching action of chlorine is due to 
Bleaching action of chlorine is due to oxidation in presence of moisture. It is permanent
Colouring matter + | O | → colourless matter
Which would quickly absorb oxygen ? [1991, 92]
Alkaline solution of pyrogallol absorbs oxygen quickly.
Oleum is 
Oleum is H2S2O7 ( H2SO4 + SO3) which is obtained by dissolving SO3 in H2SO4 and is called fuming sulphuric acid.
Aqueous solution of ammonia consists of
Aqueous solution of ammonia is obtained by passing NH3 in H2O which gives NH4+ and OH– ions.
P2O5 is heated with water to give 
P2O5 have great affinity for water. The final product is orthophosphoric acid.
Basicity of orthophosphoric acid is 
It is a tribasic acid all the three hydrogen atoms are ionisable. It forms three series of salts.
PCl3 reacts with water to form 
PH4I + NaOH forms 
Pure nitrogen is prepared in the laboratory by heating a mixture of 
Pure nitrogen in the lab can be obtained by heating ammonium nitrate. Ammonium nitrate is not a stable compound it dissociate to give nitrogen.
Which one of the following substance is used in the laboratory for fast drying of neutral gases?
Phosphorus pentoxide has great affinity for water. It forms ortho phosphoric acid on absorbing water
It is thus used as a powerful dehydrating or drying agent.
Number of electrons shared in the formation of nitrogen molecule is 
Nitrogen molecule is diatomic containing a triple bond between two N atoms,
Therefore, nitrogen molecule is formed by sharing six electrons.
Sugarcane on reaction with nitric acid gives
Cane sugar is oxidised to oxalic acid
Nitrogen is relatively in active element because 
N2 molecule contains triple bond between N atoms having very high dissociation energy (946 kJ mol–1) due to which it is relatively inactive.
H3PO2 is the molecular formula of an acid of phosphorus. Its name and basicity respectively are
H3PO2 is named as hypophosphorous acid.
As it contains only one P – OH group, its basicity is one.
When chlorine is passed over dry slaked lime at room temperature, the main reaction product is
chloride reacts with dry slaked lime to form bleaching power.
the actual composition of bleaching power is
In the manufacture of bromine from sea water, the mother liquor containing bromides is treated with
Bromide in the mother liquor is oxidised to Br2 by Cl2 which is a stronger oxidising agent.