Which statement is incorrect about peptide bond?
(a) C-N bond length in proteins is longer than usual bond length of C-N bond.
(b) Spectroscopic analysis shows planar structure of -CO-NH- group
(c) C-N bond length in proteins is smaller than usual bond length of C-N bond
(d) None of the above
(a) C-N bond length in proteins is longer than usual bond length of C-N bond.
(b) Spectroscopic analysis shows planar structure of -CO-NH- group
(c) C-N bond length in proteins is smaller than usual bond length of C-N bond
(d) None of the above
(a) C-N bond length in proteins is longer than usual bond length of C-N bond.
The reason for double helical structure of DNA is operation of-
(a) electrostatic attractions
(b) dipole-dipole interaction
(c) van der Waal’s forces
(d) hydrogen bonding
Each polypeptide in protein has amino acids linked with each other in a specific sequence. This sequence of amino acids is said to be-
(a) primary structure of proteins.
(b) secondary structure of proteins.
(c) tertiary structure of proteins.
(d) quaternary structure of proteins.
Which of the following factors is not responsible for the denaturation of proteins?
(a) Heat
(b) Charge
(c) pH change
(d) Organic solvents
RNA and DNA are chiral molecules. Their chirality is due to :
(a) Chiral bases
(b) Chiral phosphate ester units
(c) D-sugar component
(d) L-sugar component.
The letter ‘D’ in carbohydrates signifies-
(a) dextrorotatory
(b) configuration
(c) diamagnetic nature
(d) mode of synthesis
The anomeric carbon in D(+) glucose is –
(a) C-1 carbon
(b) C-2 carbon
(c) C-5 carbon
(d) C-6 carbon
The reaction R-Br + NaCN → R – CN + NaBr is an example of –
(a) Elimination Reaction.
(b) Nucleophilic Substitution.
(c) Electrophilic Substitution.
(d) Oxidation Reduction.
Aryl halides can not be prepared by the reaction of arylalcohols with \(PCl_3\), \(PCl_5\) or \(SOCl_2\) because :
(a) phenols are highly stable compounds.
(b) carbon-oxygen bond in phenols has a partial doublebond character.
(c) carbon-oxygen bond is highly polar
(d) all of these
Low concentration of oxygen in the blood and tissues of people living at high altitude is due to-
(a) low temperature
(b) low atmospheric pressure
(c) high atmospheric pressure
(d) both low temperature and high atmospheric pressure
There is a considerable increase in covalent radius from N to P. However, from As to Bi only a small increase in covalent radius is observed. This is due to
a) Increase in number of shells
b) increase in valence electrons
c) increase in ionisation enthalpy
d) the presence of completely filled d and/or f orbitals
Which of the following is incorrect for an ideal solution?
(a) \(∆H_{mix}\) =0
(b) \(∆V_{mix}\) = 0
(c) ∆P = \(P_{obs}\) – \(P_{calculated}\) = 0
(d) \(∆G_{mix}\) = 0
What happens when tertiary butyl alcohol is passed over heated copper at 300°C?
(a) Secondary butyl alcohol is formed.
(b) 2-methylpropene is formed.
(c) 1-butene is formed.
(d) Butanol is formed.
RNA and DNA are chiral molecules. Their chirality is due to :
(a) Chiral bases
(b) Chiral phosphate ester units
(c) D-sugar component
(d) L-sugar component.