Refining of silver is done by
(A) liquation
(B) poling
(C) cupellation
(D) van Arkel method
If a reaction is carried out at Constant pressure, which of the following statement is correct?
(A) The reaction is likely to be endothermic.
(B) The heat change is equal to the enthalpy change.
(C) The reaction is likely to be exothermic,
(D) (c) The heat change is equal to the change in temperature.
Galvanized iron sheets are protected from rusting due to presence of a layer of
(A) lead
(B) chromium
(C) zinc
(D) tin
Two new elements (discovered in August, 2003) with atomic number 113 and 115 are to be placed in
(A) s-block
(B) p-block
(C) d-block
(D) f-block
Which one of the following is known as salt peter?
(A) NaCI
(B) KNO3
(C) Na2CO3
(D) NaHC03
Calcium is obtained by the
(A) roasting of limestone
(B) electrolysis of solution of calcium chloride inH20
(C) electrolysis of molten anhydrous calcium chloride
(D) reduction of calcium chloride with carbon
Consider the following statements
1 . An ideal fuel should have high calorific value, low ignition temperature, regulated and controlled.
2 . Born-Haber cycle is used to determine lattice energy.
Which of the statement(s) given above is/are correct?
(A) Only 1
(B) Only 2
(C) 1 and 2
(D) None of these
Aluminium surfaces are of ten ‘anodized’. This means the deposition of a layer of
(A) chromium oxide
(B) aluminium oxide
(C) nickel oxide
(D) zinc oxide
33 . MatchColumn I with Column II .
Column I -Column II
A . Recently named by IUPAC 1 . Fe
B . Variable valency electronegativity 2 . Ds
C . Maximum 3 . Cl
D . Maximum electron affinity 4 . F
Codes
ABCD
(A) 3 2 1 4
(B) 4 3 2 1
(C) 1 4 3 2
(D) 2 1 4 3
Which one of the following is a transition metal?
(A) Aluminium (Al)
(B) Manganese (Mn)
(C) Magnesium (Mg)
(D) Calcium (Ca)
Flux is used to remove
(A) basic impurities
(B) acidic impurities
(C) all type of impurities
(D) acidic and basic both impurities
The life span of a Daniell cell may be increased by
(A) larger Zn electrode
(B) larger Cu electrode
(C) lowering the temperature
(D) lowering the concentrations
Consider the following statements
1 . Albo iron does not rust in vacuum because air is necessary for rusting.
2 . Rust is faster in sea water because of dissolved salts.
Which of the statement(s) given above is/are correct?
(A) Only 1
(B) Only 2
(C) 1 and 2
(D) None of these
Which one of the following is the correct sequence of the given substances in the decreasing order of their densities?
(A) Steel > Mercury > Gold
(B) Gold > Mercury > Steel
(C) Steel > Gold > Mercury
(D) Gold > Steel > Mercury
Bronze is often used to make statues and medals whereas brass is used in making utensils, scientific apparatus and cartridges. Both brass and bronze are copper containing alloys, yet they differ in their chemical composition for additionally containing.
(A) zinc in brass and tin in bronze
(B) chromium in brass and nickel in bronze
(C) nickel in brass and tin in bronze
(D) iron in brass and nickel in bronze
Black tin is
(A) an alloy of S n
(B) an allotrope of S n
(C) 60-70% SnO2
(D) 100% SnO2
In a hydrogen-oxygen fuel cell, combustion of hydrogen occurs to
(A) generate heat
(B) create potential difference between the two electrodes
(C) produce high purity water
(D) remove adsorbed oxygen from electrode surfaces.