The increasing order of the first ionisation enthalpies of the elements B, P, S and F (lowest first) is
The decreasing values of bond angles from (106°) to (101°) down group-15 of the periodic table is due to
increasing bond-bond pair repulsion
increasing -orbital character in
decreasing lone pair-bond pair repulsion
Following statements regarding the periodic trends of chemical reactivity of the alkali metals and the halogens are given. Which of these statements gives the correct picture?
The reactivity decreases in the alkali metals but increases in the halogens with increase in atomic number down the group
In both the alkali metals and the halogens the chemical reactivity decreases with increase in atomic number down the group
Chemical reactivity increases with increase in atomic number down the group in both the alkali metals and halogens
In alkali metals the reactivity increases but in the halogens it decreases with increase in atomic number down the group
Phenyl magnesium bromide reacts with methanol to give
a mixture of anisole and
a mixture of benzene and
a mixture of toluene and
a mixture of phenol and
The structure of the compound that gives a tribromoderivative on treatment with bromine water is
The electrophile involved in the above reaction is
Fluorobenzene can be synthesised in the laboratory
by heating phenol with and
from aniline by diazotization followed by heating the diazonium salt with
by direct fluorination of benzene with gas
by reacting bromobenzene with solution.
Reaction of trans-2-phenyl-1-bromocyclopentane on reaction with alcoholic produces
reacts with under anhydrous conditions at room temperature to give
The increasing order of the rate of addition to compounds is
Among the following the one that gives positive iodoform test upon reaction with and is
The correct order of increasing acid strength of the compounds
The term anomers of glucose refers to
isomers of glucose that differ in configurations at carbons one and four (C-1 and C-4)
a mixture of (D)-glucose and (L)-glucose
enantiomers of glucose
isomers of glucose that differ in configuration at carbon one (C-1).
The pyrimidine bases present in DNA are
cytosine and adenine
cytosine and guanine
cytosine and thymine
cytosine and uracil.
Which of the following statements is true?
is a stronger acid than
In aqueous medium HF is a stronger acid than
is a weaker acid than
is a stronger acid than
What products are expected from the disproportionation reaction of hypochlorous acid?
Which of the following factors may be regarded as the main cause of lanthanide contraction?
Poor shielding of one of electron by another in the subshell
Effective shielding of one of electrons by another in the subshell
Poorer shielding of electrons by electrons
Greater shielding of electrons by electrons
The “spin-only” magnetic moment [ in units of Bohr magneton, ] of in aqueous solution would be (atomic number of Ni = 28)
Which of the following chemical reactions depicts the oxidising behaviour of ?
The molar conductivities at infinite dilution in water at are 91.0 and 426.2 S cm2/mol respectively. To calculate , the additional value required is