Problem 16
The position of the clement in the periodic table with its outer electronic configuration \(3 \mathrm{~s}^{2} 3 \mathrm{p}^{4}\) is (1) IV period, VIB group (2) IIl period, VIA group (3) IV period, IVB group (4) IIl period, IVB group
Problem 18
The element with atomic number 84 belongs to (1) VI group, VI period (2) I group, Vl period (3) V group, VI period (4) VI group \(\mathrm{V}\) period
Problem 19
Cerium \((Z=58)\) is a member of (1) s-block elements (2) p-block elements (3) d-block elements (4) f-block elements
Problem 20
Which electronic configuration represents a transition element? (1) \(1 \mathrm{~s}^{2} 2 \mathrm{~s}^{2} 2 \mathrm{p}^{6} 3 \mathrm{~s}^{2} 3 \mathrm{p}^{6} 3 \mathrm{~d}^{10} 4 \mathrm{~s}^{2} 4 \mathrm{p}^{6}\) (2) \(1 \mathrm{~s}^{2} 2 \mathrm{~s}^{2} 2 \mathrm{p}^{6} 3 \mathrm{~s}^{2} 3 \mathrm{p}^{6} 3 \mathrm{~d}^{10} 4 \mathrm{~s}^{2} 4 \mathrm{p}^{\prime}\) (3) \(1 \mathrm{~s}^{2} 2 \mathrm{~s}^{2} 2 \mathrm{p}^{6} 3 \mathrm{~s}^{2} 3 \mathrm{p}^{6} 3 \mathrm{~d}^{2} 4 \mathrm{~s}^{2}\) (4) \(1 \mathrm{~s}^{2} 2 \mathrm{~s}^{2} 2 \mathrm{p}^{6} 3 \mathrm{~s}^{2} 3 \mathrm{p}^{6} 4 \mathrm{~s}^{2}\)
Problem 21
Which statement is false? (1) Elements of VA group are transition elements. (2) Elements of I and II groups are normal elements. (3) Elements of zero group are monoatomic gases. (4) A1l transition elements are metals.
Problem 22
Among the following pairs of atomic numbers, the pair which belongs to \(p\) -block is (1) 8,16 (2) 4,8 (3) 6,12 (4) 12,24
Problem 23
In the transition elements, the incoming electron occupies \((n-1) \mathrm{d}\) sublevel in preference to (1) \(\mathrm{np}\) (2) \(\mathrm{ns}\) (3) \((n-1) \mathrm{d}\) (4) \((n+1) \mathrm{s}\)
Problem 24
The most common oxidation state of lanthanides in their compounds is (1) \(+2\) (2) \(+3\) (3) \(+4\) (4) \(+1\)
Problem 25
The false statement regarding transition elements is (1) they exhibit variable valence (2) they form coloured compounds or ions which are paramagnetic (3) the elements and their compounds are diamagnetic (4) the clements and their compounds act as catalysts
Problem 26
Which of the following statement is wrong? (1) Transition elements lie between III and IV groups in the periodic table. (2) Transition elements are those which contain incomplete d-orbital. (3) The 14 elements placed in the 3rd group and 6 th period of the periodic table are known as rare earths. (4) The clement californium belongs to actinide series.
