Silver crystallises in f.c.c. Lattice. It edge length of the unit cells is 4.07 × \(10^{–8}\) cm density and ism 10.5g \(cm^{–3}\). Calculate the atomic mass of silver.
(A) 144 g/mol
(B) 125 g/mol
(C) 106.6 g/mol
(D) 213 g/mol
(A) 144 g/mol
(B) 125 g/mol
(C) 106.6 g/mol
(D) 213 g/mol
(C) 106.6 g/mol
The total number of tetrahedral voids in the face centred unit cell is _____.
(A) 6
(B) 8
(C) 10
(D) 12
The lattice site in a pure crystal cannot be occupied by __________.
(A) Molecule
(B) Ion
(C) Electron
(D) Atom
What is the coordination number in a square close packed structure in two dimensions?
(A) 2
(B) 3
(C) 4
(D) 6
The correct order of the packing efficiency in different types of unit cells is ________.
(A) fcc < bcc < simple cubic
(B) fcc > bcc > simple cubic
(C) fcc < bcc > simple cubic
(D) bcc < fcc = simple cubic
Solid A is very hard electrical insulator in solid as well as in molten state and melts at an extremely high temperature. What type of solid is it?
(A) Ionic solid
(B) Molecular solid
(C) Covalent solid
(D) Metallic solid
Which stoichiometric defect does not change the density of the crystal?
(A) Frenkel defect
(B) Schottky defect
(C) Interstitial defect
(D) F-centres
Which of the following is true about the value of refractive index of quartz glass?
(A) Same in all directions
(B) Different in different directions
(C) Cannot be measured
(D) Always zero
Assertion: Glycine must be taken through diet.
Reason: It is essential amino acid.
A. Assertion and reason both are correct statements and reason is correct explanation for assertion.
B. Assertion and reason both are correct statements but reason is not correct explanation for assertion.
C. Assertion is correct statement but reason is wrong statement.
D. Assertion is wrong statement but reason is correct statement.
The anomeric carbon in D(+) glucose is –
(a) C-1 carbon
(b) C-2 carbon
(c) C-5 carbon
(d) C-6 carbon
Which is the correct statement?
a) valence shell electronic configuration of group 16 elements is \(ns^1\)\(np^4\).
b) the elements of group 16 have lower ionisation enthalpy values compared to those of Group 15 in the corresponding periods.
c) Oxygen atom has more negative electron gain enthalpy than sulphur.
d) oxygen has the highest electronegativity value amongst the elements.
The idea that promoted to Bartlett to prepare first ever compound of Noble gases was
a) Low bond dissociation enthalpy of F-F bond in \(F_2\).
b) High bond enthalpy of Xe-F bond.
c) Ionization enthalpies of \(O_2\) and Xe are almost same.
d) None of the above.
A compound is formed by two elements M and N. The element N forms ccp lattice and atoms of M occupy two atoms an Mercury 1/3rd of tetrahedral voids. What is the formula of the compound?
(A) \(MN_2\)
(B) \(M_2\)\(N_3\)
(C) \(M_3\)\(N_2\)
(D) \(M_2\)\(N_2\)
Which is the most reactive towards SN1 reaction –
a) \(C_6\)\(H_5\)\(CH_2\)Cl.
b) \(C_6\)\(H_5\)CH(\(C_6\)\(H_5\))Br.
c) \(C_6\)\(H_5\)CH(\(CH_3\))Br.
d) \(C_6\)\(H_5\)C(\(CH_3\))(\(C_6\)\(H_5\))Br.
The lowest boiling point of helium is due to its
a) Inertness
b) Gaseous nature
c) Weak van der Waals force between atoms
d) electronic configuration