Problem 59
SI units of coefficient of viscosity are (a) \(\mathrm{kg} \mathrm{s}^{-1} \mathrm{~m}^{-2}\) (b) \(\mathrm{g} \mathrm{m}^{-1} \mathrm{~s}^{-1}\) (c) \(\mathrm{kg} \mathrm{m}^{-1} \mathrm{~s}^{-1}\) (d) \(\mathrm{kg} \mathrm{cm}^{-1} \mathrm{~s}^{-1}\)
Problem 60
Poise is a unit of (a) viscosity (b) vapour pressure (c) surface tension (d) parachore value
Problem 61
Which of the following is the correct relation between enthalpy of vaporization (Joule/mole) and boiling point of a liquid? (a) \(\Delta \mathrm{H}=1.5 \mathrm{P}_{\mathrm{b}}\) (b) \(\Delta \mathrm{H}=77 \mathrm{~T}\) (c) \(\Delta \mathrm{H}=88 \mathrm{~T}_{\mathrm{b}}\) (d) \(\Delta \mathrm{H}=0.5 \mathrm{~T}_{\mathrm{b}}\)
Problem 62
Which of the following liquid has the highest vapour pressure or is most volatile? (a) HF (1) (b) \(\mathrm{NH}_{3}\) (1) (c) \(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}(\mathrm{l})\) (d) \(\mathrm{H}_{2} \mathrm{O}\)
Problem 63
The vapour pressure of the liquid depends upon (a) the amount of liquid taken (b) the temperature of the liquid (c) the volume of the vessel (d) both amount and temperature (e) all of these
Problem 64
When a liquid is evaporated (a) temperature of liquid decreases (b) temperature of the liquid increases (c) liquid molecules become more energetic (d) both (b) and (c)
Problem 65
When a liquid is heated (a) surface tension increases (b) surface tension is lowered (c) viscosity increases (d) surface tension is not effected
Problem 66
A substance \(\mathrm{A}_{\mathrm{x}} \mathrm{B}_{\mathrm{y}}\) crystallizes in a face-centred cubic (FCC) lattice in which atoms 'A' occupy each corner of the cube and atoms 'B' occupy the centres of each face of the cube. Identify the correct composition of the substance \(\mathrm{A}_{\mathrm{x}} \mathrm{B}_{\mathrm{y}^{\circ}}\) (a) \(\mathrm{AB}_{3}\) (b) \(\mathrm{A}_{4} \mathrm{~B}_{3}\) (c) \(\mathrm{A}_{3} \mathrm{~B}\) (d) composition cannot be specified
Problem 67
Which of the following statements is correct in context of point defects in a crystal? (a) \(\mathrm{AgCl}\) as well as \(\mathrm{CaF}_{2}\) has Schottky defects (b) \(\mathrm{AgCl}\) as well as \(\mathrm{CaF}_{2}\) have anion Frenkel defects (c) \(\mathrm{AgCl}\) has cation Frenkel defects and \(\mathrm{CaF}_{2}\) has Schottky defects (d) \(\mathrm{AgCl}\) has cation Frenkel defects and \(\mathrm{CaF}_{2}\) has anion Frenkel defects
Problem 69
Pick out the incorrect statement: (a) \(\mathrm{NaCl}\) has \(8: 8\) coordination, while \(\mathrm{CsCl}\) is with \(6: 6\) coordination (b) In \(\mathrm{Na}_{2} \mathrm{O}\) each oxide ion is coordinated by \(8 \mathrm{Na}^{+}\) ions and each \(\mathrm{Na}^{+}\)ion by 4 oxide ions (c) \(\mathrm{NaCl}\) structure transform to \(\mathrm{CsCl}\) structure on heating (d) In \(\mathrm{CaF}_{2}\) structure, each \(\mathrm{F}^{-}\)ion is coordinated by \(4 \mathrm{Ca}^{2}\) ions and each \(\mathrm{Ca}^{+}\)ion is coordinated by \(8 \mathrm{~F}\) ions
