Description : Use the information and data given below to answer the questions Stronger intermolecular forces result in higher boiling point Strength of London forces increases with the number of electrons in the molecule ... here? (c) Why is the boiling point of HF highest while that of HCl lowest?
Last Answer : Ans :( a) In the molecules HCl, HBr and HI, dipole-dipole interaction and London forces are present. (b) Dipole moment of HCl > HBr > HI but boiling point of HCl < HBr
Description : Give one example for each of the following types of inter-particle forces (a) London dispersion forces (b)Dipole-Dipole forces (c) Hydrogen bond (d) Ion-dipole forces
Last Answer : Ans. (a) noble gases. (b) between HCl molecules. (c) Between water molecules or HF molecules. (d)Between NO3- and water molecules.
Description : What is the strongest intermolecular force present in liquid ethanol? (a) induced dipole-induced dipole (b) dipole-dipole, specifically hydrogen bonding (c) dipole-dipole, but not hydrogen bonding (d) ion-dipole
Last Answer : dipole-dipole, specifically hydrogen bonding
Description : What type of intermolecular interactions does (CH3CH2)2NH undergo? (a) induced dipole-induced dipole (b) dipole-dipole (c) hydrogen bonding (d) all of these
Last Answer : all of these
Description : Based on the intermolecular forces involved, which of the following molecules will have the lowest boiling point? w) ethane x) methyl alcohol y) methyl amine z) methyl fluoride
Last Answer : ANSWER: W -- ethane
Description : AS A GROUP, the halogens have the largest: w) atomic radii x) Boiling points y) electronegativities z) ionization energies
Last Answer : ANSWER: Y -- ELECTRONEGATIVITIES
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 : In which of the following compounds is the bonding most covalent? w) NaCl x) F2 y) MgS z) Fe3C
Last Answer : ANSWER: X -- F2
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 : Which force is most important in allowing ammonia, NH3, to dissolve in water? A hydrogen bonding B dipole-induced dipole C ion-dipole D dipole-dipole E ionic
Last Answer : A hydrogen bonding
Description : Define intermolecular forces. Also write down effect of intermolecular forces on melting points & boiling points of substances?
Last Answer : The forces of attraction present between the molecules of a compound are called Intermolecular forces''. Effect of intermolecular forces on the m.p and b.p of substances If intermolecular forces of attractions in ... . And if these forces are weak then the m.p and b.p will be relatively lower.
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 : 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.
Last Answer : Hydrogen bond formation
Description : The theory of interionic attraction attributed to Debye and Hückel: w) was disproved by Arrhenius x) accounts quantitatively for the attraction between ions in dilute aqueous solutions y) does not account for kindered "ion-activity" z) accounts for intra-molecular polar bonds
Last Answer : ANSWER: X -- ACCOUNTS QUANTITATIVELY FOR THE ATTRACTION BETWEEN IONS IN DILUTE AQUEOUS SOLUTIONS
Description : Which of the following molecules has a permanent electric dipole moment? w) H2O x) Cl2 y) CH4 z) N2
Last Answer : ANSWER: W -- H2O
Description : Define (a) Dipole-Dipole Forces (b) Avogadro law (c) Intermolecular forces
Last Answer : Ans.(a) Dipole-dipole forces : The force of attraction which act between two molecules having permanent dipoles. (b) Avogadro Law : Equal volumes of all gases under the similar condition of ... . V α n (c) Intermolecular Forces: The forces of attractions and repulsion between interacting particles.
Description : The high boiling points of alcohols, as compared to the corresponding alkanes, are due to (a) Hydrogen bonding (b) Heavy oxygen atom (c) Water solubility (d) None of these
Last Answer : Hydrogen bonding
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 : The force responsible for drops of liquid assuming a spherical shape is known as: w) strong nuclear force x) Van der Waals attraction y) surface tension z) osmotic pressure
Last Answer : ANSWER: Y -- SURFACE TENSION
Description : Which class of solids could have London Forces the attractive forces between particles in crystal lattice positions? w) ionic x) covalent y) metallic z) molecular
Last Answer : ANSWER: Z -- MOLECULAR
Description : Addition of plasticisers to polymers results in partial neutralisation of intermolecular forces of attraction between the macro-molecules thereby increasing its (A) Tensile strength (B) Chemical resistance (C) Flexibility (D) All (A), (B) & (C)
Last Answer : (C) Flexibility
Description : Which one of the following statements most accurately relates the properties of a liquid at room temperature with its vapour pressure? A A liquid with a low vapour pressure will probably have a ... with a high vapour pressure will probably have high intermolecular forces and a low boiling point.
Last Answer : A A liquid with a low vapour pressure will probably have a high surface tension and a high boiling point.
Description : Arrange the following types of interactions in correct order of their increasing strength : Covalent, hydrogen bonding, Vander Waals, dipole dipole
Last Answer : Vander Waals < dipole dipole < hydrogen bonding < covalent.
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 : pH is defined as the negative logarithm of the hydrogen ion concentration. Comparing a pH 5 and a pH 8 solution, which of the following is true? w) There are 1,000 times more hydrogen ions in ... . z) Cannot tell the difference between these two solutions by pH, since the numbers are so close.
Last Answer : ANSWER: X -- THERE ARE 1,000 TIMES MORE HYDROGEN IONS IN THE PH 5 SOLUTION
Description : Which of the following molecules or ions is NOT formed when K metal reacts with liquid CH3OH? Is it: w) potassium ion x) hydrogen ion y) methoxy ion z) hydrogen molecule
Last Answer : ANSWER: X -- HYDROGEN ION
Description : Why are dipole forces of attraction not found in halogen molecule.?
Last Answer : Feel Free to Answer
Description : Which of the following groups of elements have an OUTER ELECTRONIC configuration of S-2-P-2? w) halogens x) Nitrogen-Phosphorus Group y) Carbon-Silicon Group z) Boron-Aluminum Group
Last Answer : ANSWER: Y -- CARBON-SILICON GROUP
Description : The elements that have an outer electron configuration ns2 (read: n - s - 2) are called: w) halogens x) transition metals y) alkaline earths z) noble gases
Last Answer : ANSWER: Y -- ALKALINE EARTHS
Description : Which of the following halogens does NOT replace the other halogens from their compounds? w) fluorine x) iodine y) bromine z) chlorine
Last Answer : ANSWER: X -- IODINE
Description : The elements in group 1A of the periodic table are called: w) halogens x) alkaline earths y) alkali metals z) rare earths
Last Answer : ANSWER: Y -- ALKALI METALS
Description : Which of the following compounds has the lowest boiling points? w) CH4 x) CCl4 y) PH3 z) PCl3
Last Answer : ANSWER: W -- CH4
Description : Which of the following is NOT oxidized by chlorine? w) F- (read: F minus) x) Br- (read: B - R minus) y) F2 (read: F - 2) z) I- (read: I minus)
Last Answer : ANSWER: A -- F
Description : Why is the intermolecular attraction ball predominant if the contraction coefficient is Z
Last Answer : Z < 1 means that real gas is more compressible than standard gas. If a gas is more compressible , the intermolecular attraction between the gas particles must be greater. This is why if z < 1, the intermolecular force of attraction is greater , so that the gas becomes more compressible.
Description : All gases form what type of mixture? w) dispersion x) colloidal y) homogeneous z) heterogeneous
Last Answer : ANSWER: Y -- HOMOGENEOUS
Description : Which compound is responsible for the rotten egg smell? w) sulfuric acid x) putrescine y) hydrogen sulfide z) sulfur dioxide
Last Answer : ANSWER: Y -- HYDROGEN SULFIDE (NOTE: putrescine is a real compounz)
Description : Which of the following molecules has a dipole moment? w) BF3 x) NH3 y) CCL4 z) CH4
Last Answer : ANSWER: B -- NH3
Description : Which of the following molecules does NOT have a dipole moment of zero? w) BeCl2 x) BF3 y) CO2 z) NH3
Last Answer : ANSWER: Z -- NH3
Description : The 1936 Nobel Prize in chemistry was awarded to Peter J.W. Debye for his studies of: w) kinetic energy of colliding particles x) electron configuration y) dipole moments z) conformations of cyclohexane
Last Answer : ANSWER: Y -- DIPOLE MOMENTS
Description : For which molecule can the bonding be described in terms of sp3 hybrid orbitals of the central atom? w) CH4 x) SF6 y) BF3 z) PCL5
Last Answer : ANSWER: B -- CH4
Description : Which of the following terms refers to the number of molecules or ions attached to a central metallic atom? w) coordination number x) connection number y) bonding number z) none of these
Last Answer : ANSWER: W -- COORDINATION NUMBER
Description : Thiols are alcohol analogs in which the oxygen has been replaced by sulfur (e.g., CH3SH). Given the fact that the S-H bond is less polar than the O-H bond, which of the following ... (c) Hydrogen bonding forces would be the same. (d) No comparison can be made without additional information
Last Answer : Hydrogen bonding forces are weaker in thiols.
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 : What is the force of intermolecular attraction ?
Last Answer : The force by which molecules of matter join together to form different physical structures is called intermolecular force of attraction. The form of the intermolecular attraction ball can be different -1. Dipole-Dipole attraction ball 2. Vander Walls attraction ball 3. Hydrogen bonding , etc.
Description : A bond in which there is an unequal attraction for the shared electrons and a resultant unbalanced distribution of charge is which one of the following types of bonds? w) ionic x) pure covalent y) nonpolar covalent z) polar covalent
Last Answer : ANSWER: Z -- POLAR COVALENT
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 : 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 : Honey contain glucose and fructose along with some other ingredients, it has greater viscosity due to------? A. hydrogen bonding B. irregular shape of the molecules C. irregular shape of the molecules and strong inter-molecular forces (Answer) D. greater molecular size
Last Answer : C. irregular shape of the molecules and strong inter-molecular forces (Answer)
Description : Which type of intermolecular forces exists among the following molecules? (a) H2S molecules (b) H2O (c) Cl2 and CCl4 (d) SiH4 (e) Helium (f) He atoms and HCl molecules
Last Answer : Ans. (a) Dipole-Dipole interactions. (b)H-Bond. (c)Dispersion forces. (d)Dispersion forces. (e)Dispersion forces. (f)Induced dipole-dipole interactions.