In the brown ring test for the nitrate ion, the brown colour is due to
Options
(a) [Fe(H₂O)₅NO]²⁺ (b) [Fe(H₂O)₅NO]³⁺ (c) [Fe(H₂O)₆]⁺ (d) [Fe(H₂O)₅NO₂]²⁺
Correct Answer:
[Fe(H₂O)₅NO]²⁺
Explanation:
When an aqueous solution of […]
Which of the following sulphides when heated strongly in air gives the corresponding metal
Options
(a) Cu₂S (b) CuS (c) HgS (d) FeS
Correct Answer:
HgS
Explanation:
No explanation available. Be the first […]
Restriction endonuclease is employed for cutting
Options
(a) A single stranded DNA (b) Double stranded DNA (c) RNA fragment (d) mRNA
Correct Answer:
Double stranded DNA
Explanation:
No explanation available. Be the first […]
The reaction of an ester RCOOR’ with an alcohol R”OH in the presence of an acid gives
Options
(a) RCOOH (b) R’COOH (c) R”COOR (d) RCOOR”
Correct Answer:
RCOOR”
Explanation:
No explanation available. […]
In an NPN transistor the collector current is 24 mA. If 80% of the electrons reach collector, its base current in mA is
Options
(a) 36 (b) 26 (c) 16 (d) 6
Correct Answer: […]
Complete the reaction: ₀n¹+ ₉₂U²³⁵→₅₆Ba¹⁴⁴+……..+3n
Options
(a) ₃₆Kr⁸⁹ (b) ₃₆Kr⁹⁰ (c) ₃₆Kr⁹³ (d) ₃₆Kr⁹²
Correct Answer:
₃₆Kr⁸⁹
Explanation:
A’ of product of be formed = (235 + 1) – (144 +3) = 236 – […]
If the ionisation energy for the hydrogen atom is 13.6 eV, the energy required to excite it from the ground state to the next higher state is nearly
Options
(a) 3.4 eV (b) […]
Suppose for some reasons, radius of earth were to shrink by 1% of present value, mass remaining same, then g(acceleration due to gravity), will change by
Options
(a) Nil (b) 1% (c) -1% […]
A sound source is moving towards a stationary listener with 1/10th of the speed of sound. The ratio of apparent to real frequency is
Options
(a) (10/9) (b) (10/9)² (c) (11/10)² (d) (11/10)
A carnot engine working between 300 K and 600 K has a work output of 800J per cycle. The amount of heat energy supplied to the engine from the source in each cycle is
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