the tenth element in the periodic table resembles:
(1) it is a fact.
Which of the following order is not in accordance with the property stated against it ?
(a) F2 > Cl2 > Br2 > l2 Oxidising Power
(b) Hl > HBr >HCl >HF Acidic property in water
(c) F2 > Cl2 > Br2 > l2 Electronegativity
(d) F2 > Cl2 > Br2 > l2 Bond dissociation energy
SInce size increases down the period , thus bond dissociation energy decreases.
An element X occurs in short period having configuration ns2np1 . The formula and nature of its oxide are:
(a) XO3, basic
(b) XO3, acidic
(c) X2O3, amphoteric
(d) X2O3, basic
(c) B2O3, Al2O3 are amphoteric oxides
The outermost electronic configuration of the most electronegative element is :
(c) It belongs to general outer electronic configuration of halogens which are most electronegative elements.
The elements X, Y, Z and J have the indicated electron configurations starting with the innermost shell. The most metallic element is :
(a) X = 2, 8, 3
(b) Y = 2, 8, 8
(c) Z = 2, 8, 8, 1
(d) j = 2, 8, 8, 7
(c) The metallic character is maximum in I gp. elements.
Which statement is true?
(1) the electronegative nature of elements increases along the period
(2) the electropositive nature of elements increases along the period
(3) the chemical reactivity of elements increases along the period
(4) the chemical reactivity of element decreases along the period
(1) it is a fact.
The most non-metallic element among the following is:
(b) Non-metallic character increases along the period and decreases down the gp.
58Ce is a member of:
(a) s-block elements
(b) p-block elements
(c) d-block elements
(d) f-block elements
(d) Elements from atomic number 58 to 71 are f-block elements and are known as Lanthanoids or rare earths.
The screening effect of 'd' electrons is :
(a) much less than s-electrons
(b) much more than s-electrons
(c) equal to s-electrons
(d) equal to p-electrons
(a) Screening effect order for sub-shell is of a shell, s>p>d>f.
Transuranic elements are those which are:
(a) of higher atomic number than uranium
(b) lighter than uranium
(c) of lower atomic number than uranium
(d) of same atomic number as uranium
(a) It is a fact.