Description : What is also true of the rearrangement of atoms?
Last Answer : The amount of matter is conserved.
Description : In the Hofmann-Bromamide rearrangement intermediate compounds are:
Last Answer : In the Hofmann-Bromamide rearrangement intermediate compounds are: A. `R -CONHBr` B. `[R-overset(O)overset(||)(C)- ... ` C. `R -N=C=O` D. all of these
Description : Which of the following is not a possible reaction of a carbocation? (a) addition of a nucleophile (b) rearrangement to a more stable carbocation (c) addition of a proton to form an alkane (d) loss of a β-hydrogen to form an alkene
Last Answer : addition of a proton to form an alkane
Description : True or false .During a chemical change atoms are lost or gained to the new substance?
Last Answer : FALSE
Description : The VNTRs in DNA fingerprinting stand for a. Versatile New Tandem Rearrangement b. Various Number of Transverse Repeat c. Variable New Transvers Regions d. Variable Number of Tandem Repeats
Last Answer : d. Variable Number of Tandem Repeats
Description : Hofmann rearrangement In the Hofmann rearrangement an unsubstituted amide is treated with sodium hydroxide and bromide to give a primary amine that ha
Last Answer : Hofmann rearrangement In the Hofmann rearrangement an unsubstituted amide is treated with sodium hydroxide and bromide to ... . `II gt I gt IV gt III`
Last Answer : Hofmann rearrangement In the Hofmann rearrangement an unsubstituted amide is treated with sodium hydroxide and bromide to ... O)overset(||)(C)-NH_(2)`
Description : In which of the following reacations is there a possibility of rearrangement?
Last Answer : In which of the following reacations is there a possibility of rearrangement? A. `S_(N^(1))` B. `S_(N^(2))` C. `E_(1)` D. `E_(2)`
Description : Which are related with Curtius rearrangement?
Last Answer : Which are related with Curtius rearrangement? A. `NaN_(3)` B. `R-NH_(2)` C. `R-overset(O)overset(||)(C)-CI` D. `R-overset(O)overset(||)(C)-OH`
Description : Conversion of pepsinogen to pepsin is (A) Intra molecular rearrangement (B) Breaking of hydrogen bonds (C) Covalent modification (D) Polymerisation
Last Answer : Answer : C
Description : Cells become variable in morphology and function in different regions of the embryo. The process is (a) differentiation (b) metamorphosis (c) organisation (d) rearrangement.
Last Answer : (a) differentiation
Description : --------rearrangement give the product of Cine substitution. a. Wittig b. Von Richter c. Rupe d. Lossen
Last Answer : b. Von Richter
Description : ----rearrangement involves alpha diketone. a. Wolf b. Schmidt c. Hofmann d. Curtius
Last Answer : a. Wolf
Description : If atoms with electronegativitu differences higher than 1.7 generally form ionic bonds true or false?
Last Answer : Need answer
Description : The law of conservation of mass states that in a chemical reaction, matter can be created or destroyed true or false?
Last Answer : the answer for apex if False
Description : True or false The law of conservation of mass states that in a chemical reaction, matter can be created or destroyed?
Last Answer : 1
Description : It is important to balance the chemical equations to satisfy the law of conservation of mass. Which of the following statements of the law is incorrect? (a) The total mass of the elements present in ... the reaction (d) Mass can neither be created nor can it be destroyed in a chemical Reaction.
Last Answer : Answer : (c) The chemical composition of the reactants is the same before and after the reaction
Description : In a chemical reaction, __________ are conserved. (A) Ions (B) Masses (C) Atoms (D) Both (B) & (C)
Last Answer : (D) Both (B) & (C)
Description : The property of carbon atoms to form long chains in compounds is called
Last Answer : catenation.
Description : Those substances which have so far not been resolved by any means into other substances of simpler form are called A. elements B. compounds C. atoms D. molecules
Last Answer : Answer: A
Description : What is a chemical reaction in which compounds break up into simpler constituents?
Last Answer : It is a decomposition reaction.For example: What is the decomposition reaction for water?H2O(l) --> H2(g) + O2(g)
Description : Ionic non polar solid dielectrics contain more than one type of atoms but no permanent dipoles. State True/False a) True b) False
Last Answer : a) True
Description : Atoms with four valence electrons are good conductors. (A) True (B) False
Last Answer : (B) False
Description : Organic compounds are formed under some vital force. True or false. Explain.
Last Answer : Organic compounds are not formed under vital force is false because earlier they thought that organic compounds could not be prepared in the laboratory. In 1828 Friedrich Wohler prepared urea, a typical product
Description : (a) Show on a diagram the transfer of electrons between the atoms in the formation of MgO. Write symbols of cation and anion present in MgO. (b) Name the solvent in which ionic compounds are generally soluble. (c) Why are aqueous solutions of ionic compounds able to conduct electricity? -Chemistry
Last Answer : (b) Ionic compounds are soluble in water. (c) It is because aqueous solutions consist of ions which can move freely in them and carry current.
Description : (a) Show the formation of Na2O by the transfer of electrons between the combining atoms. (b) Why are ionic compounds usually hard? (c) How is it that ionic compounds in the solid state do not conduct electricity but they do so when in molten state? -Chemistry
Last Answer : (b) It is due to strong force of attraction between oppositely charged ions. (c) In solid state, ions are not free to move whereas in molten state ions are free to move, therefore, they conduct electricity in molten state.
Description : Electronegativity of carbon atoms depends upon their state of hybridisation. In which of the following compounds, the carbon marked with asterisk is m
Last Answer : Electronegativity of carbon atoms depends upon their state of hybridisation. In which of the following compounds, the ... 2)-overset(**)CH_(2)-CH_(3)`
Description : What compounds that contain both carbon and hydrogen atoms?
Last Answer : They are organic compounds; specifically, they are hydrocarbons.
Description : What types of atoms are ionic compounds?
Last Answer : Ionic compounds contain a metal ans a nonmetal.
Description : Compounds of carbon having double or triple bonds between their carbon atoms are called (1) Saturated compounds (2) Unsaturated compounds (3) Reactive compounds (4) None of the above
Last Answer : (2) Unsaturated compounds Explanation: Compounds of carbon, which are linked by only single bonds between the carbon atoms are called saturated compounds. Compounds of carbon having double or triple bonds between their carbon atoms are called unsaturated compounds.
Description : Organic compounds having same molecular formula with different structural arrangement of atoms in them is known as
Last Answer : isomerism.
Description : What do you call the compounds having the same molecular formula but different structural arrangements of atoms?
Last Answer : Isomers
Description : Elements are made of -----? A. Atoms (Answer) B. Molecules C. H2O D. Compounds
Last Answer : A. Atoms (Answer)
Description : Two compounds have the same composition and also have the same atoms attached to the same atoms, although with different orientations in space. These compounds are (a) Identical (b) Position isomers (c) Structural isomers (d) Stereoisomers
Last Answer : Stereoisomers
Description : Which of the following is not a characteristic of organic compounds? (a) They usually have low melting points. (b) They usually are only slightly soluble or insoluble in water. (c) If water ... they seldom conduct an electric current. (d) Bonds which bind the atoms together are nearly always ionic.
Last Answer : Bonds which bind the atoms together are nearly always ionic.
Description : The first line of host defense is the barrier presented to the external environment. Which of the following statement(s) is/are true concerning host barriers? a. Sebaceous glands secrete ... of the upper gastrointestinal tract d. Gut peristalsis serves to prevent microbial adherence and invasion
Last Answer : Answer: b, c, d The skin, mucus membranes, and epithelial layers of various organs of the body constitute effective physical barriers against microbial invasion. In certain portions of the ... very low pH within the stomach and gut peristalsis both serve to prevent microbial adherence and invasion
Description : Which of the following is false? (1) Most carbon compounds are poor conductors of electricity. (2) The force of attraction between carbon molecules is not very strong. (3) The atomic number of carbon is 6. (4) The earth’s crust has about 2% carbon in the form of minerals.
Last Answer : (4) The earth’s crust has about 2% carbon in the form of minerals.
Description : (3) the number of electrons orbiting around the nucleus Explanation: The chemical behavior of an atom is determined by the number of electrons on its outer shell. As for the chemical bonding properties of ... , and in what ratio atoms will bond to form the 20,000,000 different substances on Earth.
Last Answer : Methyl phenyl ether can be obtained by reacting - (1) phenolate ions and methyl iodide (2) methoxide ions and bromobenzene (3) methanol and phenol (4) bromobenzene and methyl bromide
Description : In a backward chaining system you start with the initial facts, and keep using the rules to draw new conclusions (or take certain actions) given those facts. a) True b) False
Last Answer : b) False
Description : Which of these statements is false All atoms are alike. All electrons are alike. All neutrons are alike. All protons are alike.?
Last Answer : True statements: All neutrons are alike, all electrons are alike, all protons are alike (All atoms of a given isotope is only alike). False statement: All atoms are alike All atoms are not alike as they may vary in the number of protons / electrons / neutrons.
Description : Which of the following statements is false about tautomers? (a) Tautomers are structural isomers (b) Tautomers are structural isomers which exist in dynamic equilibrium (c) Tautomerism involves movement of atoms (d) Tautomers have independent existence
Last Answer : Tautomers have independent existence
Description : The chemical reactivity of noble gases involves the loss of electrons and hence it can form compounds with highly electronegative elements like F and
Last Answer : The chemical reactivity of noble gases involves the loss of electrons and hence it can form compounds with ... )d` and linear D. `sp` and linear
Last Answer : The chemical reactivity of noble gases involves the loss of electrons and hence it can form compounds with highly ... D. `sp^(3)d^(2)` & 2
Last Answer : The chemical reactivity of noble gases involves the loss of electrons and hence it can form compounds with highly ... A. zero B. 2 C. 6 D. 8
Description : Waste gases from industrial plants form acids that hasten chemical weathering. Most of the gases are compounds of: w) argon x) hydrogen y) iron z) sulfur
Last Answer : ANSWER: Z -- SULFUR
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 : The energy required to start an enzymatic reaction is called (A) Chemical energy (B) Metabolic energy (C) Activation energy (D) Potential energy
Description : In a physical change some of the first physical properties of the substance may be altered and the chemical composite remains the same true or false?
Last Answer : The chemical composition is unchanged.
Description : What True or false the most important agent of chemical weathering is abrasion?