D. Carbonyl group reduction in monosaccharides leads to corresponding acids.
C. When 2-butyne is hydrogenated in the presence of palladium poisoned with lead salts, the obtained product presents geometrical isomers.
B. A mixture of acetone and propanal (5.8 g), which contains 20% acetone, reacts by heterogeneous catalysis with 2.24 l of hydrogen.
E. Hydrogenation reactions are specific to hydrocarbons containing multiple bonds.
A. The same compound is obtained from the hydrogenation reaction of maleic or fumaric acid
D. Maleic anhydride is obtained by benzene oxidation.
C. 2-ketopentanoic acid and oxalic acid are obtained when 1-methyl-1,4-cyclohexadiene is oxidized with KMnO4, in the presence of sulphuric acid.
B. When alcohols are oxidized with potassium permanganate, in the presence of sulphuric acid, the colour of the reaction mixture turns form orange to green.
E. Cupric hydroxide oxidizes glucose.
A. Oxidation of tert-butanol with potassium dichromate, in the presence of sulphuric acid, leads to butanoic acid.
B. 2,7-Octanedione is obtained by the oxidation of 1,2-dimethyl-1-cyclohexadiene with K2Cr2O7 and H2SO4.
D. p-aminobenzoic acid can be obtained by the oxidation of p-aminobenzaldehyde with potassium permanganate in the presence of sulphuric acid.
C. Partial oxidation of petrol fuel (gasoline) can yield carbon monoxide.
E. Synthesis of alkenes from alkanes is an oxidation process.
A. When isoprene is oxidized with K2Cr2O7 and H2SO4, the reaction products are the ketopropionic acid, CO2 and H2O.
B. The products formed by incomplete oxidation are compounds with a lower number of carbon atoms.
D. The oxidation reaction is reversible.
A. 48 g of oxygen are obtained at 100% yield from 1 mole of K2Cr2O7 in the presence of H2SO4, in the presence of a reducing agent.
C. When naphthalene and o-xylene are oxidized with the same volume of oxygen, the working mass ratio between naphthalene and o-xylene is 0.805.
E. Mild oxidation of tertiary alcohols yields an acid.
B. The solution resulting after its dissolution in water has an alkaline character.
D. It is a salt.
A. It is a detergent.
E. It is an ionic substance.
C. It contains two types of anions.
C. Primary aliphatic amines are stronger bases compared to secondary aliphatic amines.
B. The basicity of amines is modified radically depending on the carbon type involved in the bond (primary, secondary or tertiary).
E. Diphenylamine is a secondary amine.
A. Amines are weaker bases compared to ammonia.
D. N,N-dimethyl-phenylamine is a stronger base compared to diphenylamine.
B. When a small quantity of acetic acid is added.
D. When small amounts of ammonia and acetic acid are added (1:1 molar ratio).
E. None of the answers A-D are true.
A. When a small quantity of ammonia is added.
C. When a small quantity of 2-aminopropionic acid is added.
A. Hydrogen and sulphur are organogenic elements.
D. Quantitative analysis of carbon and hydrogen in organic compounds produces substances with identical molecular mass.
E. The atomic ratio of the glucose molecule is C:H:O=1:2:1.
C. The percent composition of formaldehyde and lactic acid (alpha-hydroxy-propionic acid) is identical.
B. The percent composition of ammonium cyanate and urea is identical.
D. 5-Ethynyl-2-methyl-3-vinyl-1,3,6-heptatriene contains primary, secondary, tertiary and quaternary carbon atoms.
A. Cyclohexane and cyclopropane contain only secondary carbon atoms.
C. 2,3,4-Trimethylpentane does not contain quaternary carbon atoms
B. Ethyl-cyclopentane contains primary, secondary and tertiary carbon atoms.
E. Phenyl-ethane contains five secondary carbon atoms.
E. There are 5 sigma bonds in ethene.
D. In alcohols, oxygen is involved in two sigma bonds.
A. The formula CnH2n-2 corresponds to an alkyne, alkadiene, cycloalkyne.
B. Monoelectronic orbitals may exist only in the fundamental state of elements.
C. Interatomic distances represent the sum of the atomic diameters of bonded atoms.
A. Nitrogen may be involved in simple, double and triple covalent bonds.
E. Carbon is involved only in double covalent bonds.
C. The hydrocarbon having the molecular mass of 58 is saturated.
B. In the homogenous covalent bonds, the bond energy increases from the simple to the triple bond.
D. The length of the covalent bond increases from the simple to the triple bond.
E. In alkanes, the involved carbon atoms are only hybridized sp3.
A. The presence of asymmetric carbon atoms in the structure of substances decreases their number of isomers.
C. Decreasing the number of carbon atoms in the structure of organic substances increases their number of isomers.
D. In multiple covalent heterogeneous bonds, the involved carbon atoms may be hybridized sp and sp2.
B. One of the validity criteria of the molecular formula is that the sum of all covalencies of the component elements must be an odd number.
B. 4 branched carbon chain isomers
A. 3 linear carbon chain isomers
E. 6 isomers in total
D. 3 isomers with tertiary carbon atoms
C. 5 aldehydes isomers
E. Glycine may present mesoforms.
C. They do not rotate the plane of polarized light.
D. 2,3-diaminobutane may present optical active configurations as well as mesoforms
A. They contain asymmetric carbon atoms.
B. They have a symmetry plane.
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