Description : The noble gases have low boiling points because: w) their ionization potentials are very low x) only weak Van der Waals forces hold the atoms together y) they are produced by the fractional distillation of liquid air z) they have eight electrons in the outer shell
Last Answer : ANSWER: X -- ONLY WEAK VAN DER WAALS FORCES HOLD THE ATOMS TOGETHER
Description : The atoms in sugar are bound by what type of bond? w) ionic x) hydrogen y) covalent z) van der Waals
Last Answer : ANSWER: Y -- COVALENT
Description : Forces in ionic crystalline solids are primarily which of the following? w)covalent x)electrostatic y)Van der Waals z)magnetic
Last Answer : ANSWER: X -- ELECTROSTATIC
Description : Why do alcohols have boiling points much higher than hydrocarbons of similar molecular weight? (a) Alcohols have greater van der Waals attraction forces. (b) Alcohol molecules have greater ... of volatilization. (d) Alcohols must overcome greater ionic forces in the process of volatilization.
Last Answer : Hydrogen bonds must be broken in the process of volatilization
Description : Diamond is hard because (a) It has strong covalent bonds (b) Discrete molecules of carbon are held by strong Vander Waal’s forces (c) It involves Van der Waal's forces (d) Covalent bonds are directional unlike ionic bonds
Last Answer : Ans:(a)
Description : Van der Waals derived an expression for the pressure defect', if the observed pressure is denoted as p' and volume is denoted as V', the gas pressure in the bulk of the gas is equal to: A. p + ... a: constant for the particular gas D. p + (a V²); where a: constant for the particular gas
Last Answer : p + a/(V²); where a: constant for the particular gas
Description : Internal energy of a gas obeying Van-Der-Waals equation of state, [p + (a/v2)] (V - b) = RT, depends upon its (A) Pressure & temperature (B) Pressure & specific volume (C) Temperature & specific volume (D) Temperature only
Last Answer : (A) Pressure & temperature
Description : Which of the following best explains why the melting points of saturated fats increase with increasing molecular weight? (a) decreased hydrogen bonding (b) increased hydrogen bonding (c) decreased intermolecular van der Waal’s interactions (d) increased intermolecular van der Waal’s interactions
Last Answer : increased intermolecular van der Waal’s interactions
Description : Which action best accounts for the solubility of aldehydes and ketones in water? (a) Polar interactions between solute molecules. (b) H-bonding between solute molecules. (c) Van der waals forces (d) H-bonding between solute and solvent molecules
Last Answer : H-bonding between solute and solvent molecules
Description : Which of the following is the strongest interaction? (a) a covalent bond (b) dipole-dipole interactions (c) hydrogen bonding (d) van der Waals
Last Answer : a covalent bond
Description : The fluid property which matters for falling rain drops to acquire spherical shape is its (A) Pressure (B) Height of descend (C) Viscosity (D) Surface tension
Last Answer : (D) Surface tension
Description : Name type of adsorption in which van der Waals forces are present.
Last Answer : Name type of adsorption in which van der Waals forces are present.
Description : Pick the wrong statement: hydrogen bonding results in (a) Increased solubility in water (b) Higher Van der Waal's forces (c) Molecular association (d) Abnormal boiling point
Last Answer : Ans:(b)
Description : Van der Waals equation explains the behaviour of (a) Mixture of gases (b) Ideal gas (c) Real gas (d) Water gas
Last Answer : Ans:(c)
Description : Chemisorption (chemical adsorption) is (A) Same as "Van der Waals" adsorption (B) Characterised by adsorption of heat (C) An irreversible phenomenon (D) A reversible phenomenon
Last Answer : (C) An irreversible phenomenon
Description : Covalent network crystals have-------? A. higher melting point then molecular crystals (Answer) B. lower melting point then molecular crystals C. discrete molecules linked by Van der waals forces D. hydrogen bonding
Last Answer : A. higher melting point then molecular crystals (Answer)
Description : Which types of chemical bonds are the weakest? a. covalent c. ionic b. Van der Waals d. none of the above
Last Answer : b. Van der Waals
Description : Surface tension of a liquid (A) Is due to intermolecular forces of cohesion (B) Decreases with rise in temperature (C) Is responsible for the spherical shape of an isolated liquid drop (D) All (A), (B) & (C)
Last Answer : (D) All (A), (B) & (C)
Description : Rain drops acquire spherical shape due to - (1) viscosity (2) surface tension (3) friction (4) elasticity
Last Answer : (2) surface tension Explanation: The Surface tension pulls the surface of the drop equally at all points thus produces the spherical shape having the minimum surface area.
Description : A falling drop of rain water ac-quires the spherical shape due to – (1) Viscosity (2) Surface Tension (3) Atmospheric pressure (4) Gravitational force
Last Answer : (2) Surface Tension Explanation: Raindrops start out as round high in the atmosphere as water collects on dust and smoke particles in clouds. But as raindrops fall, they lose their rounded ... the molecules stick together. The cause is the weak hydrogen bonds that occur between water molecules.
Description : A falling drop of rain water acquires the spherical shape due to (1) Viscosity (2) Surface Tension (3) Atmospheric pressure (4) Gravitational force
Last Answer : Surface Tension
Description : Surface tension of liquids is the result of which the following: w) interaction of a liquid with its container x) unbalanced forces on the liquid's surface molecules y) adhesive forces of the liquid z) interaction of the liquid's surface molecules and the applied pressure
Last Answer : ANSWER: X -- UNBALANCED FORCES ON THE LIQUID'S SURFACE MOLECULES
Description : Rain drops are spherical because of (A) Viscosity (B) Air resistance (C) Surface tension forces (D) Atmospheric pressure
Last Answer : Answer: Option C
Description : Why liquid drops are spherical in shape?
Last Answer : Ans. Because of surface tension, the molecules tend to minimize the surface area and sphere has minimum surface area.
Description : A drop of liquid assumes spherical shape because: (1) Intermolecular forces are strong in liquids (2) A sphere has the least surface area for a given volume (3) A sphere has the largest surface area for a given volume (4) Inter molecular forces are weak in liquids
Last Answer : (2) A sphere has the least surface area for a given volume Explanation: A drop of liquid assumes spherical shape because a sphere has the least surface area for a given volume.
Last Answer : A sphere has the least surface area for a given volume
Description : Water drops are spherical because of - (1) viscosity (2) density (3) polarity (4) surface tension
Last Answer : (4) surface tension Explanation: Surface tension is responsible for the shape of liquid droplets. Although easily deformed, droplets of water tend to be pulled into a spherical shape by ... absence of other forces, including gravity, drops of virtually all liquids would be approximately spherical.
Description : The boiling points of the halogens increase going from F2 to I2. What type of intermolecular forces are responsible for this trend? w) permanent dipole x) hydrogen bonding y) ion-ion attraction z) London dispersion forces
Last Answer : ANSWER: Z -- LONDON DISPERSION FORCES
Description : Which of the following properties is lower for a solution than for the pure solvent? w) osmotic pressure x) vapor pressure y) temperature z) boiling point
Last Answer : ANSWER: X -- VAPOR PRESSURE
Description : One property a colloidal dispersion has that a solution does not is: w) homogeneity x) filterability y) the Tyndall effect z) osmotic pressure
Last Answer : ANSWER: Y -- THE TYNDALL EFFECT
Description : The Grand Unified Theory of the forces of nature combines three of the four forces. Which force is NOT included? w) gravitational x) electromagnetic y) weak nuclear z) strong nuclear
Last Answer : ANSWER: W -- GRAVITATIONAL
Description : The difference in the osmotic pressures of one molar solutions of different compounds in a given solvent at a given temperature results from? w) Different values for R x) Different values for Avogadro's number y) Ionization or dissociation z) None of the above
Last Answer : ANSWER: Y -- IONIZATION OR DISSOCIATION
Description : Spherical shape of mercury droplets is due to its (A) High viscosity (B) Low surface tension (C) High density (D) High surface tension
Last Answer : Option D
Description : Two bodies each have a mass 'M'. If the mass of each body is doubled, the force of attraction between the two bodies is: w) twice the original force x) 1/4 the original force y) 4 times the original force z) unchanged
Last Answer : ANSWER: Y -- 4 TIMES THE ORIGINAL FORCE
Description : If the distance between the earth and moon were halved, the force of the attraction between them would be: w) one fourth as great x) one half as great y) twice as great z) four times as great
Last Answer : ANSWER: Z -- FOUR TIMES AS GREAT
Description : Two steel balls are at a distance S from one another. As the mass of ONE of the balls is doubled, the gravitational force of attraction between them is: w) quartered x) halved y) doubled z) quadrupled
Last Answer : ANSWER: Y -- DOUBLED
Description : If the distance between two objects, each of mass 'M', is tripled, the force of attraction between the two objects is: w) 1/2 the original force x) 1/3 the original force y) 1/9 the original force z) unchanged
Last Answer : ANSWER: Y -- 1/9 THE ORIGINAL FORCE
Description : Which of the following is the term used for the resistance of a liquid system to flow? w) surface tension x) diffusion y) viscosity
Last Answer : ANSWER: Y -- VISCOSITY
Description : Bacterial cells susceptible to penicillium can be protected from destruction if the medium in which they are exposed is of A- high osmotic pressure B- low osmotic pressure C- moderate osmotic pressure D- high surface tension
Last Answer : high osmotic pressure
Description : A pure drug is administered as a sphere and as a cube. The amount of drug is the same in the two tablets. Assuming that the shape and size do not influence the mass transfer, the ratio of rate of dissolution in water at t ... tablet is: (A) 0.54 (B) 1.04 (C) 1.24 (D) 1.94
Last Answer : (C) 1.24
Description : What reflecting surface forms a geometrically perfect image of a point source located at infinity (such as that approximated by a star)? w) Paraboloid x) Ellipsoid y) spherical z) Hyperboloid
Last Answer : ANSWER: W -- PARABOLOID
Description : Assuming all other parameters remain constant, what happens to the pressure of a gas when the volume of the gas is increased? w) increases x) decreases y) fluctuates sinusoidally z) remains the same
Last Answer : ANSWER: X -- DECREASES
Description : Spherical shape of rain drops can be ex- plained by?
Last Answer : Surface tension of water
Description : Why the rain drops acquired the spherical shape?
Last Answer : Surface tension
Description : Water drops cannot stick to the oily surface due to – (1) lack of adhesive force (2) surface tension (3) cannot mix each other (4) water is lighter than oil
Last Answer : (2) surface tension Explanation: The separation of oil and water is caused due to the difference in surface tension of the two liquids. The water molecules stick together tightly and does not mix ... to each other very strongly, forming an invisible "skin" of surface tension around each drop.
Description : Rain drops falling through atmospheric air attain limited terminal velocity, because of (A) Upward thrust due to air (B) Viscous force exerted by air (C) Surface tension effects of water (D) Force of gravity
Last Answer : Option B
Description : Water drops cannot stick to the oily surface due to (1) lack of adhesive force (2) surface tension (3) cannot mix each other (4) water is lighter than oil
Last Answer : surface tension
Description : When two ice cubes are pressed together, they join to form one cube. Which one of the following helps to hold them together? (1) Hydrogen bond formation (2) Vander waals forces (3) Covalent attraction (4) Dipole interaction
Last Answer : (1) Hydrogen bond formation Explanation: When two ice cubes are pressed together, they join to form one cube due to hydrogen bond.