MUNISH KAKAR’s INSTITUTE OF CHEMISTRY
PERIODIC TABLE & PROPERTIES
Q1.
What are Eka aluminium and Eka silicon ?
Q2.
What are characteristics of s - , p- , d- and f - block elements ?
Q3.
Why formation of fluoride ion is exothermic while that of oxide ion is endothermic ?
Q4.
Why CaO is basic in nature while P2O5 is acidic in nature ?
Q5.
How many groups and how many periods in periodic table begin ?
Q6.
Why fourth period contains 18 elements while sixth period contains 32 elements ?
Q7.
Why do noble gases have bigger atomic size than halogens?
Q8.
Define ‘ionization enthalpy’.How does ionization energy vary (i) down the group, (ii) along
the period from left to right?
Q9.
Why are cations smaller than neutral atom while anions are bigger than neutral atom ?
Q10. Which out of the N or O has higher negative electron gain enthalpy?
Q11. Which out of F or Cl has a more negative electron gain enthalpy? Explain.
Q12. Among the elements B, Al, C and Si:
(a) which has the highest first ionization enthalpy?
(b) which has most negative electron gain enthalpy?
(c) which has the largest atomic radius?
(d) which has the most metallic character?
Q13. Why IE1 of (i) 7N is greater than 8O (ii)
13Al
is less than
12Mg
?
Q14. The first ionization energy of carbon atom is greater than that of boron whereas tha
reverse is true for the second ionization energy. Explain.
Q15. Among the second period elements the actual ionization enthalpies are in the order Li < B
< Be < C < O < N < F < Ne.
Explain why:
(a) Be has higher iH than B?
(b) O has lower iH than N and F?
Q16. The first ionization enthalpy values (in kJ mol-1) of group 13 elements are:
B
Al
Ga
In
Tl
801
577
579
558
589
Why Ionization energy of Ga , In and Tl is larger tha expected ?
Q17. Explain why the second ionization energy of B is significantly higher than the second
ionization energy of C, even though the first ionization energy of B is less than C.
Q18. The first(IE1) and second (IE2) ionization enthalpies (kJ mol-1) of three elements I, II and III
are given below:
S.C.O. No. 203, SECOND FLOOR, SECTOR 14, PANCHKULA. Phone : 9417655033, 9888019721
MUNISH KAKAR’s INSTITUTE OF CHEMISTRY
I
II
III
IE1
403
549
1142
IE2
2640
1060
2080
Identify the elements which is likely to be (a) non-metal (b) an alkali metal (c) an alkaline
earth metal.
Q19. The first (iH1) and the second (iH2) ionization enthalpies (in kJ mol-1) and the (egH)
electron gain enthalpy (in kJ mol-1) of a few elements are given below:
Elements
H1
H2
egH
I
520
7300
-60
II
419
3051
-48
III
1681
3374
-328
IV
1008
1846
-295
V
2372
5251
+48
VI
738
1451
-40
Which of the above elements is likely to be:
(a) the least reactive elements
(b) the most reactive elements
(c) the most reactive non-metal
(d) the least reactive non-metal.
(e) the metal which can form stable binary halide of the formula MX2 (X = halogen)
(f) the metal which can form a predominantly stable covalent halide of the formula MX?
Q20.
(a) Account for the following :
(i) Mg+2 ion is smaller tha O2- ion although both have same electronic structure.
(ii) Ionisation enthalpy of nitrogen is more than that of oxygen.
(b) Write the IUPAC name and the symbol for the element with at. no. 118.
S.C.O. No. 203, SECOND FLOOR, SECTOR 14, PANCHKULA. Phone : 9417655033, 9888019721