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CBSE Class 10 Science
Chapter -5
PERIODIC CLASSIFICATION OF ELEMENTS
1.
X, Y and Z are the elements of a dobereiners triad. If
the atomic mass of x is 7 and that of z is 39, what should be the atomic mass
of y?
Ans.
y = 23.
2.
A and B are the two elements having similar properties
which obey Newlands law of octaves. How many elements are there in between A
and B?
Ans. Six elements.
3.
The following is Newland's Octave Table. Observe it and
answer the following Questions:
|
Sa(do) |
re(re) |
ga(mi) |
ma (fa) |
pa(so) |
da (la) |
ni(ti) |
|
H |
Li |
Be |
B |
C |
N |
O |
|
F |
Na |
Mg |
Al |
Si |
P |
S |
|
Cl |
K |
Ca |
Cr |
Ti |
Mn |
Fe |
|
Co and Ni |
Cu |
Zn |
Y |
In |
As |
Se |
|
Br |
Rb |
Sr |
Ce and La |
Zr |
- |
- |
i.
Which of the element in 1st column has different
properties from rest of the elements?
ii.
Which of the elements resemble with each other in second
column?
iii.
Pick up odd element in second last column.
iv.
Pick up elements which have similar properties in last
column.
Ans. (a) Co & Ni (b) Li, Na, K (c) Mn
(d) O.S.Se
4.
In the Periodic Table given below, Lithium, carbon,
oxygen and neon are placed in their correct positions and the positions of nine
other elements are represented by letters. These letters are not the symbols
for the elements?
|
1 |
2 |
13 |
14 |
15 |
16 |
17 |
18 |
|
Lithium |
|
|
Carbon |
|
Oxygen |
L |
Neon |
|
X |
|
|
E |
|
G |
Q |
|
|
Y |
|
|
|
|
|
R |
|
|
Z |
|
|
|
|
|
T |
|
5.
By reference to the table, answer the following
questions:
a.
Give the letter of the most reactive metal.
b.
Give the letter of the most reactive non-metal.
c.
Name the family of elements represented by L, Q, R, and
T.
d.
Name one element in each case occurring in groups 2, 13
and 15
Ans.
a.
Z
b.
L
c.
Halogen
family
d. Mg(group-2), Al (group-13), N(group-15)
For More Questions Download PDF File: Download Here
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