Description : All chiral D-sugars rotate plane-polarized light : (a) clockwise (b) counterclockwise (c) +20.0° (d) in a direction that cannot be predicted but must be determined experimentally
Last Answer : in a direction that cannot be predicted but must be determined experimentally
Description : Which of the statements is false regarding chiral compounds? (a) rotate the plane of polarized light (b) have cis and trans isomers (c) exist as enantiomers (d) can be detected with a polarimeter
Last Answer : have cis and trans isomers
Description : Which of the following is a true statement? (a) All chiral molecules possess a plane of symmetry. (b) All achiral molecules are meso. (c) All molecules which possess a single asymmetric center of the S configuration are levorotatory. (d) A mixture of achiral compounds will be optically inactive
Last Answer : A mixture of achiral compounds will be optically inactive
Description : Which of the following statements is correct concerning a pair of enantiomers? (a) They rotate the plane of polarized light by exactly the same amount and in opposite directions. (b) They rotate ... polarized light by differing amounts and in the same direction. (d) They have different melting point
Last Answer : They rotate the plane of polarized light by exactly the same amount and in opposite directions.
Description : Which of the statements below correctly describes an achiral molecule? (a) The molecule has a nonsuperimposable mirror image. (b) The molecule exhibits optical activity when it interacts with plane-polarized light. (c) The molecule has an enantiomer. (d) The molecule might be a meso form
Last Answer : The molecule might be a meso form
Description : Consider (R)- and (S)-2-butanol. Which physical property distinguishes the two compounds? (a) melting point (b) solubility in common solvents (c) Rotation of plane-polarized light (d) Infrared spectrum
Last Answer : Rotation of plane-polarized light
Description : Which of the following statements is false about enantiomers? (a) rotate plane-polarized light (b) are superimposable mirror images (c) are nonsuperimposable mirror images (d) have the same melting point
Last Answer : are superimposable mirror images
Description : An optically active compound (a) must contain atleast four carbons (b) when in solution rotate the plane of polarized light (c) must always contain an asymmetric carbon atom (d) in solution always give a negative reading in polarimeter
Last Answer : when in solution rotate the plane of polarized light
Description : A meso compound : (a) is an achiral molecule which contains chiral carbons (b) contains a plane of symmetry or a centre of symmetry (c) is optically inactive (d) is characterized by all of the above
Last Answer : ) is characterized by all of the above
Description : A molecule is said to be chiral (a) if it contains plane of symmetry (b) if it contains centre of symmetry (c) if it cannot be superimposed on its mirror image (d) if it can be superimposed on its mirror image
Last Answer : if it cannot be superimposed on its mirror image
Description : The reddish hue of the Sun at sunset is due to the fact that (a) Sunlight is polarized horizontally when scattered by molecules of the atmosphere (b) Light of short wavelength is ... than light of long wavelength (d) Sunlight is polarized vertically when scattered by molecules of the atmosphere
Last Answer : Ans:(b)
Description : What are biomolecules? Are they different from the molecules of the lifeless matter? -Biology
Last Answer : answer:
Description : How are large organic molecules (biomolecules) synthesized?
Last Answer : Feel Free to Answer
Description : Optically active compounds are capable of (A) Different reactions (B) Rotating plane of polarized light (C) Showing same chemical properties (D) None of these
Last Answer : Answer : B
Description : Chiral molecules are :
Last Answer : Chiral molecules are : A. Superimposable on their mirro image B. Not superimposable on ... molecules D. capable of showing geometrical isomerism
Description : Which of the following are chiral molecules
Last Answer : Which of the following are chiral molecules
Description : An electromagnetic wave is ________ polarized when the electric field lies wholly in one plane containing the direction of propagation. A. Horizontally B. Linearly C. Circularly D. Vertically
Last Answer : B. Linearly
Description : Electromagneticwaves are refractedwhen they a. pass into a medium of different dielectric constant b. are polarized at right angles to the direction of propagation c. encounter a perfectly conducting plane d. pass through a small slot in a conducting plane
Last Answer : a. pass into a medium of different dielectric constant
Description : The designation D or Lbefore the name of a monosaccharide (a) indicates the direction of rotation of polarized light. (b) indicates the length of the carbon chain in the carbohydrate. (c) ... the primary alcohol group. (d) indicates the position of the asymmetric carbon atoms in the carbohydrate.
Last Answer : indicates the position of the OH group on the carbon next to the primary alcohol group.
Description : Polymers are (A) Micro-molecules (B) Macromolecules (C) Sub-micromolecules
Last Answer : (B) Macromolecules
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 : Thermosetting resins are those polymers, which (A) Do not increase in plasticity with rise in temperature (B) Allow slip to occur between molecules (C) Do not take on a permanent set (D) None of these
Last Answer : (A) Do not increase in plasticity with rise in temperature
Description : Glycine is a unique amino acid because it (a) has no chiral carbon (b) has a sulfur containing R group (c) cannot form a peptide bond (d) is an essential amino acid
Last Answer : has no chiral carbon
Description : Which of the following compounds is never chiral? (a) 2,3-dibromobutane (b) 1,3-dibromobutane (c) 1,2-dichlorobutane (d) 1,4-dibromobutane
Last Answer : 1,4-dibromobutane
Description : What is the name given to the non-superimposable mirror image forms of chiral compounds? w) cis-trans x) enantiomers y) functional isomers z) diasteriomers
Last Answer : ANSWER: X -- ENANTIOMERS
Description : Which of these waves can be polarized? (1) Sound waves in air (2) Longitudinal waves on a string (3) Transverse waves on a string (4) Light waves
Last Answer : (4) Light waves Explanation: It is possible to transform unpolarized light into polarized light. A light. wave that is vibrating in more than one plane is referred to as unpolarized light. Polarized light waves are light waves in which the vibrations occur in a single plane.
Description : ______ is a device that detects both vertically and horizontally polarized signals simultaneously. A. Crystal B. Orthomode transducer C. Light transducer D. Optoisolator
Last Answer : B. Orthomode transducer
Description : The conditions for the production of constructive and destructive interference are reversed due to the fact that on striking the thin film -------. A. Two rays of splitted light undergo phase ... two rays of splitted light undergo phase change of 180° C. Light is diffracted, light is polarized
Last Answer : A. Two rays of splitted light undergo phase change of 180°
Description : Of the following, the type of wave that CANNOT be polarized is w) electromagnetic x) light y) sound z) radio
Last Answer : ANSWER: Y -- SOUND
Description : Which of these waves can be polarized ? (1) Sound waves in air (2) Longitudinal waves on a string (3) Transverse waves on a string (4) Light waves
Last Answer : Light waves
Description : How do biomolecules differ from biomacromolecules? -Biology
Description : $ Minerals such as carbonates and phosphates acts as buffers. ! Biomolecules contain only 25 elements out of the 109 known elements.
Last Answer : $ Minerals such as carbonates and phosphates acts as buffers. ! Biomolecules contain only 25 elements out of ... wrong D. If both As and R are wrong.
Description : Assertion: The study of biomolecules is called Molecular biology. Reason: Cell is a type of molecule.
Last Answer : Assertion: The study of biomolecules is called Molecular biology. Reason: Cell is a type of molecule. A. If ... wrong D. If both As and R are wrong.
Description : What biomolecules are in eggs?
Last Answer : because of science
Description : The most abundant biomolecules on earth
Last Answer : Ans. Carbohydrates
Description : Consider the following biomolecules: 1. Vitamin A 2. Enzyme 3. Testosterone 4. DNA The biomolecules that are made in the human body are: (a) 1, 2 and 4 only (b) 1, 3 and 4 only (c) 2, 3 and 4 only (d) 1, 2 and 3 only
Last Answer : Ans:(c)
Description : What is the nature of the interactions between biomolecules?
Last Answer : Interactions between biomolecules depend on the forming and breaking of chemical bonds. The covalent bond is the strongest chemical bond. It links individual atoms within a molecule and ... specificity, and response to water. Although noncovalent interactions are weaker than covalent bonds .
Description : DNA precipitation out of a mixture of biomolecules can be achieved by treatment with (a) chilled chloroform (b) isopropanol (c) chilled ethanol (d) methanol at room temperature.
Last Answer : (c) chilled ethanol
Description : Which of the following biomolecules is common to respiration-mediated breakdown of fats, carbohydrates and proteins? (a) Glucose-6-phosphate (b) Fructose 1, 6-bisphosphate (c) Pyruvic acid (d) Acetyl CoA
Last Answer : d) Acetyl CoA
Description : Which of the following biomolecules does have a phosphodiester bond? (a) Amino acids in a polypeptide (b) Nucleic acids in a nucleotide (c) Fatty acids in a diglyceride (d) Monosaccharides in a polysaccharide
Last Answer : b) Nucleic acids in a nucleotide
Description : Which one of the following biomolecules is correctly characterized? (a) Lecithin-a phosphorylated glyceride found in cell membrane. (b) Palmitic acid - an unsaturated fatty acid with 18 carbon atoms. ... Alanine amino acid - contains an amino group and an acidic group anywhere in the molecule.
Last Answer : (a) Lecithin-a phosphorylated glyceride found in cell membrane
Description : Match the column I with column II. Column-I Column-II A. Golgi apparatus (i) Synthesis of protein B. Lysosomes (ii) Trap waste and excretory products C. Vacuoles (iii) Formation of glycoproteins and glycolipids D. Ribosomes (iv) Digesting ... ), C-(iv), D-(i) (d) A-(i), B-(ii), C-(iv), D-(iii)
Last Answer : (a) A-(iii), B-(iv), C-(ii), D-(i)
Description : Metabolism is referred to as (1) synthesis of biomolecules (2) breaking-down of biomolecules (3) synthesis and breaking down of biomolecules (4) recycling of biomolecules
Last Answer : synthesis and breaking down of biomolecules
Description : Which of the following is correct regarding AIDS causative agent HIV? (a) HIV is enveloped virus containing one molecule of single-stranded RNA and one molecule of reverse transcriptase. (b) HIV ... ) HIV is unenveloped retrovirus. (d) HIV does not escape but attacks the acquired immune response
Last Answer : (d) HIV does not escape but attacks the acquired immune response.
Description : During an early step of respiration, glucose is converted into two identical molecules of: a) CO2 b) ATP c) pyruvic acid(pron: pie-ROO-vik) d) chlorophyll
Last Answer : ANSWER: C -- PYRUVIC ACID
Description : A block A is dropped down a smooth inclined plane, while another identical block B is released for free fall from the same height a.block A will have higher velocity than block B while hitting the ... . c.both will hit the ground simultaneously d.block A will hit the ground earlier e.107 dynes
Last Answer : b. block B will hit the ground earlier.
Description : A boy sitting in a rail road car throws a ball straight up into the air. The ball will fall back into his hands when the rail road car is a.moving at constant velocity b.accelerating ... inclined plane, while another identical block B is released for free fall from the same height e.decelerating
Last Answer : a. moving at constant velocity
Description : A block slides down a smooth inclined plane when released from the top while another falls freely from the same point. The value of which parameter in the two cases will be identical? a.Time ... ground c.Momentum at the ground d.Velocity while touching the ground e.Kinetic energy after one second
Last Answer : d. Velocity while touching the ground
Description : When any plane passing through the central axis of the of the body divides the organism into two identical halves, it is radial symmetry. Which of the
Last Answer : When any plane passing through the central axis of the of the body divides the organism ... ctenophores, echinoderms D. Annelids, arhtropods, housefly
Description : Two dimensional flows occurs when (A) The direction and magnitude of the velocity at all points are identical (B) The velocity of successive fluid particles, at any point, is the same at ... fluid particles move in plane or parallel planes and the streamline patterns are identical in each plan
Last Answer : Answer: Option D