21390.The correct order of bond angles (smallest first) in H2S,NH3, BF3 and SiH4 is:
H2S < SiH4 < NH3 < BF3
NH3 < H2S < SiH4 < BF3
H2S < NH3 < SiH4 < BF3
H2S < NH3 < BF3 < SiH4
21391.Which of the following is not correct regarding the properties of ionic compounds
Ionic compounds have high melting and boiling points.
Their reaction velocity in aqueous medium is very high.
Ionic compounds in their molten and aqueous solutions do not conduct electricity.
They are highly soluble in polar solvents.
21392.In the anion HCOO– the two carbon–oxygen bonds are found to be of equal length. What is the reason for it?
Electronic orbitals of carbon atom are hybridised
The C=O bond is weaker than the C–O bond
The anion HCOO– has two resonating structures
The anion is obtained by removal of a proton from the acid molecule
21395.In case of heteronuclear diatomics of the type AB, where A is more electronegative than B, bonding molecular orbital resembles the character of A more than that of B. The statement
is false
is true
can not be evaluated since data is not sufficient
is true only for certain systems
21396.Consider the molecules CH4, NH3 and H2O. Which of the given statements is false?
The H–O–H bond angle in H2O is smaller than the H–N–H bond angle in NH3
The H–C–H bond angle in CH4 is larger than the H–N–H bond angle in NH3
The H–C–H bond angle in CH4, the H–N–H bond angle in NH3, and the H–O–H bond angle in H2O are all greater than 90°
The H–O–H bond angle in H2O is larger than the H–C–H bond angle in CH4
21397.Which one of the following is a correct set?
H2O, sp3,angular
H2O, sp2, linear
NH+
4, dsp2, square planar
4, dsp2, square planar
CH4, dsp2,tetrahedral
21398.The structure of XeF6 is experimentally determined to be distorted octahedron. Its structure according to VSEPR theory is
Octahedron
Trigonal bipyramid
Pentagonal bipyramid
Tetragonal bipyramid