Depression of Freezing Point
CHXII02:SOLUTIONS

319084 1.0 g of a non-electrolyte solute (molar mass \({\rm{250}}{\mkern 1mu} {\mkern 1mu} {\rm{g}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}\)) was dissolved in 51.2 g of benzene. If the freezing point depression constant of benzene is \({\rm{5}}{\rm{.12}}{\mkern 1mu} {\mkern 1mu} {\rm{K}}{\mkern 1mu} {\mkern 1mu} {\rm{kg}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}\), the lowering in freezing point will be

1 0.2 K
2 0.3 K
3 0.5 K
4 0.4 K
CHXII02:SOLUTIONS

319085 A 5% solution (by mass) of cane sugar in water has freezing point of 271K. Calculate the freezing point of 5% glucose in water if freezing point of water is 273.15K

1 269.07K
2 \({\rm{269}}{\rm{.0}}{{\rm{7}}^{\rm{^\circ }}}{\rm{C}}\)
3 373K
4 \({\rm{37}}{{\rm{3}}^{\rm{^\circ }}}{\rm{C}}\)
CHXII02:SOLUTIONS

319086 Calculate the molal depression constant of naphthalene in usual units if enthalpy of fusion is \({\rm{19192}}{\rm{.3}}{\mkern 1mu} {\mkern 1mu} {\rm{J}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}\). Pure naphthalene melts at 353.1 K. Molecular mass of naphthalene is
\({\rm{128 \times 1}}{{\rm{0}}^{{\rm{ - 3}}}}{\rm{kg}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}{\mkern 1mu} {\mkern 1mu} \left( {{\rm{R = 8}}{\rm{.314}}{\mkern 1mu} {\mkern 1mu} {\rm{J}}{{\rm{K}}^{{\rm{ - 1}}}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}} \right)\)

1 1.86
2 6.9
3 5.12
4 12.8
CHXII02:SOLUTIONS

319087 Camphor is often used in molecular mass determination because

1 it is readily available
2 it has a very high cryoscopic constant
3 it is volatile in nature
4 it is solvent for organic substances
CHXII02:SOLUTIONS

319084 1.0 g of a non-electrolyte solute (molar mass \({\rm{250}}{\mkern 1mu} {\mkern 1mu} {\rm{g}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}\)) was dissolved in 51.2 g of benzene. If the freezing point depression constant of benzene is \({\rm{5}}{\rm{.12}}{\mkern 1mu} {\mkern 1mu} {\rm{K}}{\mkern 1mu} {\mkern 1mu} {\rm{kg}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}\), the lowering in freezing point will be

1 0.2 K
2 0.3 K
3 0.5 K
4 0.4 K
CHXII02:SOLUTIONS

319085 A 5% solution (by mass) of cane sugar in water has freezing point of 271K. Calculate the freezing point of 5% glucose in water if freezing point of water is 273.15K

1 269.07K
2 \({\rm{269}}{\rm{.0}}{{\rm{7}}^{\rm{^\circ }}}{\rm{C}}\)
3 373K
4 \({\rm{37}}{{\rm{3}}^{\rm{^\circ }}}{\rm{C}}\)
CHXII02:SOLUTIONS

319086 Calculate the molal depression constant of naphthalene in usual units if enthalpy of fusion is \({\rm{19192}}{\rm{.3}}{\mkern 1mu} {\mkern 1mu} {\rm{J}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}\). Pure naphthalene melts at 353.1 K. Molecular mass of naphthalene is
\({\rm{128 \times 1}}{{\rm{0}}^{{\rm{ - 3}}}}{\rm{kg}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}{\mkern 1mu} {\mkern 1mu} \left( {{\rm{R = 8}}{\rm{.314}}{\mkern 1mu} {\mkern 1mu} {\rm{J}}{{\rm{K}}^{{\rm{ - 1}}}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}} \right)\)

1 1.86
2 6.9
3 5.12
4 12.8
CHXII02:SOLUTIONS

319087 Camphor is often used in molecular mass determination because

1 it is readily available
2 it has a very high cryoscopic constant
3 it is volatile in nature
4 it is solvent for organic substances
CHXII02:SOLUTIONS

319084 1.0 g of a non-electrolyte solute (molar mass \({\rm{250}}{\mkern 1mu} {\mkern 1mu} {\rm{g}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}\)) was dissolved in 51.2 g of benzene. If the freezing point depression constant of benzene is \({\rm{5}}{\rm{.12}}{\mkern 1mu} {\mkern 1mu} {\rm{K}}{\mkern 1mu} {\mkern 1mu} {\rm{kg}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}\), the lowering in freezing point will be

1 0.2 K
2 0.3 K
3 0.5 K
4 0.4 K
CHXII02:SOLUTIONS

319085 A 5% solution (by mass) of cane sugar in water has freezing point of 271K. Calculate the freezing point of 5% glucose in water if freezing point of water is 273.15K

1 269.07K
2 \({\rm{269}}{\rm{.0}}{{\rm{7}}^{\rm{^\circ }}}{\rm{C}}\)
3 373K
4 \({\rm{37}}{{\rm{3}}^{\rm{^\circ }}}{\rm{C}}\)
CHXII02:SOLUTIONS

319086 Calculate the molal depression constant of naphthalene in usual units if enthalpy of fusion is \({\rm{19192}}{\rm{.3}}{\mkern 1mu} {\mkern 1mu} {\rm{J}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}\). Pure naphthalene melts at 353.1 K. Molecular mass of naphthalene is
\({\rm{128 \times 1}}{{\rm{0}}^{{\rm{ - 3}}}}{\rm{kg}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}{\mkern 1mu} {\mkern 1mu} \left( {{\rm{R = 8}}{\rm{.314}}{\mkern 1mu} {\mkern 1mu} {\rm{J}}{{\rm{K}}^{{\rm{ - 1}}}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}} \right)\)

1 1.86
2 6.9
3 5.12
4 12.8
CHXII02:SOLUTIONS

319087 Camphor is often used in molecular mass determination because

1 it is readily available
2 it has a very high cryoscopic constant
3 it is volatile in nature
4 it is solvent for organic substances
CHXII02:SOLUTIONS

319084 1.0 g of a non-electrolyte solute (molar mass \({\rm{250}}{\mkern 1mu} {\mkern 1mu} {\rm{g}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}\)) was dissolved in 51.2 g of benzene. If the freezing point depression constant of benzene is \({\rm{5}}{\rm{.12}}{\mkern 1mu} {\mkern 1mu} {\rm{K}}{\mkern 1mu} {\mkern 1mu} {\rm{kg}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}\), the lowering in freezing point will be

1 0.2 K
2 0.3 K
3 0.5 K
4 0.4 K
CHXII02:SOLUTIONS

319085 A 5% solution (by mass) of cane sugar in water has freezing point of 271K. Calculate the freezing point of 5% glucose in water if freezing point of water is 273.15K

1 269.07K
2 \({\rm{269}}{\rm{.0}}{{\rm{7}}^{\rm{^\circ }}}{\rm{C}}\)
3 373K
4 \({\rm{37}}{{\rm{3}}^{\rm{^\circ }}}{\rm{C}}\)
CHXII02:SOLUTIONS

319086 Calculate the molal depression constant of naphthalene in usual units if enthalpy of fusion is \({\rm{19192}}{\rm{.3}}{\mkern 1mu} {\mkern 1mu} {\rm{J}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}\). Pure naphthalene melts at 353.1 K. Molecular mass of naphthalene is
\({\rm{128 \times 1}}{{\rm{0}}^{{\rm{ - 3}}}}{\rm{kg}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}{\mkern 1mu} {\mkern 1mu} \left( {{\rm{R = 8}}{\rm{.314}}{\mkern 1mu} {\mkern 1mu} {\rm{J}}{{\rm{K}}^{{\rm{ - 1}}}}{\mkern 1mu} {\mkern 1mu} {\rm{mo}}{{\rm{l}}^{{\rm{ - 1}}}}} \right)\)

1 1.86
2 6.9
3 5.12
4 12.8
CHXII02:SOLUTIONS

319087 Camphor is often used in molecular mass determination because

1 it is readily available
2 it has a very high cryoscopic constant
3 it is volatile in nature
4 it is solvent for organic substances