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 : 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 : 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 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : 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 : The following type of bonding is strongly directional in solids. (A) Vander Waal's (B) Ionic (C) Metallic (D) Covalent
Last Answer : D) Covalent
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 : 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 : What type of bonding is most important in CH3CH2CH2CH2CH2CH3? (a) ionic (b) hydrogen (c) covalent (d) polar
Last Answer : covalent
Description : Sodium chloride, potassium chloride, magnesium oxide are examples of molecules with (a) Covalent bonding (b) Ionic bonding (c) Metallic bonding (d) Hydrogen bonding
Description : For _______ bonding, one or more electrons are transferred between atoms. a. hydrogen b. ionic c. peptide d. covalent
Last Answer : b. ionic
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 : 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 : Which of the following has a multiple covalent bond? w) Bromine x) Hydrogen y) Oxygen z) Chlorine Monofluoride
Last Answer : ANSWER: Y -- OXYGEN
Description : The bond in hydrogen chloride is which of the following types? Is it w) ionic x) nonpolar covalent y) polar covalent z) covalent network
Last Answer : ANSWER: Y -- POLAR COVALENT
Description : Can you imagine how the Holloway family is feeling tonight as Joran van der Sloot was arrested today?
Last Answer : How sad that another girl had to lose her life at the hands of this monster before he was brought in. Aruba should have put him on trial instead of letting his father buy off the officials. ... another innocent young lady. Only they can know what the other parents are going through at this time.
Description : Who played James Van Der Beek's girlfriend on Medium tonight?
Last Answer : The actress who played pre-crash Harmony was Dahlia Salem, but the actress who played post-reconstruction “Brooke” was Morena Baccarin.
Description : Before he turned physics upside down, a young Albert Einstein supposedly showed off his genius by devising a complex riddle involving a stolen exotic fish and a long list of suspects. Can you resist ... written by one of the smartest people in history? Dan Van der Vieren shows how. -Riddles
Last Answer : The key is that the person at the back of the line who can see everyone else's hats can use the words 'black' or 'white' to communicate some coded information. So what meaning can be assigned ... . And every time this happens, the next person in line will switch the parity they expect to see.
Description : how to find the price of a print by rogier van der weyden
Last Answer : Need Answer
Description : How did van der weyden's paintings differ from those of other artist of his name?
Last Answer : Feel Free to Answer
Description : How did van der Weyden painting differ from those of other artist of his time?
Last Answer : He incorporated emotion into his compositions (apex)
Description : Look at the central panel of the portinari alterpiece by hugo van der goes. this artwork uses all of the following execpt what?
Last Answer : the trompe illusion
Description : Look at this painting by rogier van der wetden. The composition of this painting is intended to?
Last Answer : intensify the emotional effect (.apex)
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 : 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 : Explain in brief about hydrophobic interactions in antigen-antibody interaction ?
Last Answer : Contribute up to 50% of the total strength of antigen- antibody interactions. These reactions are found when ever the side chains of non-polar amino acids of antigen-antibody come together.
Description : Explain in brief about Vander Val interactions in antigen-antibody interaction ?
Last Answer : Temporary transfer of electrons from one molecule to another will result in the force of attraction between them. This is seen when the interacting molecules come close to each other.
Description : Political unrest, budget overruns, size and complexity of the project Answer: B (8)Decision trees are best used for : 1. Determining the interaction of the amount at stake and the expected ... and the associated events 4. A flow chart which determines the standard deviation of the risk event
Last Answer : 3. An illustration of how to see the interactions between decisions and the associated events
Description : ________________ causes pharmacodynamic drug interaction. a) Gastric motility changes. b) Stimulation of metabolism. c) Alteration of pH of GIT. d)Interactions at receptor site.
Last Answer : d)Interactions at receptor site.
Description : The angle between the bonding orbitals of a molecules `AX_(3)` with zero dipole moment is
Last Answer : The angle between the bonding orbitals of a molecules `AX_(3)` with zero dipole moment is A. `120^(º)` B. `109^(º)` C. `104^(º)` D. `180^(º)`
Description : What is dipole dipole bonding?
Last Answer : too