In which of the following pairs of molecules/ions, the central atoms have sp²-hybridisation?
Options
(a) NO₂⁻ and NH₃ (b) BF₃ and NO₂⁻ (c) NH₂⁻ and H₂O (d) BF₃ and NH₂⁻
Correct Answer:
BF₃ […]
Which of the following molecules has trigonal planar geometry?
Options
(a) BF₃ (b) NH₃ (c) PH₃ (d) IF₃
Correct Answer:
BF₃
Explanation:
(a) BF₃ ⇒ 3bp + 0/p ⇒ sp³ -hybridisation and triagonal […]
Which one of the following species does not exist under normal conditions?
Options
(a) Be₂⁺ (b) Be₂ (c) B₂ (d) Li₂
Correct Answer:
Be₂
Explanation:
Bond order of Be₂ is zero hence it […]
The set representing the correct order for the first ionisation potential is
Options
(a) K > Na > Li (b) Be > Mg > Ca (c) B > C > N (d) Ge […]
Which one is electron deficient compound?
Options
(a) NH₃ (b) ICl (c) BCl₃ (d) PCl₃
Correct Answer:
BCl₃
Explanation:
BCl₃ has six electrons in outer shell of boron atom.
Correct order of first IP among following elements Be, B, C, N, O is
Options
(a) B< Be < C
A trend common to both for group I and VII elements in the periodic table as atomic number increases is
Options
(a) atomic radius increases (b) oxidising power increases (c) reactivity with water […]
Which of the following pairs show reverse properties on moving along a period from left to right and from top to down in a group?
Options
(a) Nuclear charge and electron affinity (b) […]
One of the characteristic properties of non-metals is that they
Options
(a) Are reducing agents (b) Form basic oxides (c) Form cations by electron gain (d) Are electro negative
Correct Answer:
Are reducing […]
1 c.c N₂O at NTP contains
Options
(a) (1.8/224) x 10²² atoms (b) (6.02/22400) x 10²³ molecules (c) (1.32/224) x 10²³ electrons (d) all the above
Correct Answer:
all the above
Explanation:
At N.T.P […]
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