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
Chemical reactivity increases with increase in atomic number down the group in both the alkali metals and halogens
In a multi-electron atom, which of the following orbitals described by the three quantum numbers will have the same energy in the absence of magnetic acid and electric fields?
(a) n = 1, l = 0, m = 0
(b) n = 2, l = 0, m = 0
(c) n = 2, l = 1, m = 1
(d) n = 3, l = 2, m = 1
(e) n = 3, l = 2, m = 0
(a) and (b)
(b) and (c)
(c) and (d)
(c) and (d)
In which of the following arrangements the order is NOT according to the property indicated against it?
Al3+ < Mg2+ < Na+ < F- Increasing ionic size
B < C < N < O Increasing first ionization enthalpy
I < Br < F < Cl Increasing electron gain enthalpy (with negative sign)
I < Br < F < Cl Increasing electron gain enthalpy (with negative sign)
Which of the following statements in relation to the hydrogen atom is correct?
3s orbital is lower in energy than 3p orbital
3p orbital is lower in energy than 3d orbital
3s and 3p orbitals are of lower energy than 3d orbital
3s and 3p orbitals are of lower energy than 3d orbital
Which one the following ions has the highest value of ionic radius?
Li+
F-
O2-
O2-
C.
O2-
The decreasing order of basic character of K2O, BaO, CaO and MgO is
K2O > BaO > CaO > MgO
K2O > CaO > BaO > MgO
MgO > BaO > CaO > K2O
MgO > CaO > BaO > K2O
In case of heteronuclear diatomics of the type AB, where A is more electronegative than B, bonding molecular orbital resembles the character of A more than that of B. The statement
is false
is true
cannot be evaluated since data is not sufficient
is true only for certain systems
The ground state electronic configuration of CO molecule is
1σ22σ2143σ2
1σ22σ23σ21222
1σ22σ2123σ222
1σ2122σ22σ2