ICSE
CHEMISTRY
Class 9
The Period table – Worksheet 1
1. As per the Mendeleev’s periodic law the Physical and Chemical properties of elements are the periodic functions of :
A) Atomic number
B) Atomic weight
C) Atomicity
D) both B and C
2. The group of elements which belongs to Dobereiner’s triads:
(atomic weights are given in brackets)
A) Na(23), Al(27), K(39)
B) Li(7), Na(23), K(39)
C) Li(7), Na(23), Ca (40)
D) Be (9), Na(23), Ca(40)
3. The Dobereiner’s triad theory for the classification of elements was discarded because:
A) the theory was not holding true for all elements
B) the elements grouped into triads were not found to be similar
C) many elements were not found by that time
D) both A and B
4. According to Dobereiner the elements in a triad were arranged such that:
A) they are in the increasing order of their atomic weight
B) the atomic wt of the middle element is the average of the other two elements
C) they have similar properties
D) all of the above
5. Newland’s law of octaves :
A) The elements are arranged in the increasing order of their atomic weight
B) The elements are arranged in series of eight
C) every eighth element resembles with the first element in its physical and chemical properties
D) all of the above
6. The Newland’s law of octaves failed :
A) in case of light metals metals
B) to explain the position of heavy metals
C) to leave space for undiscovered elements
D) both B and C
7. If the table given shows the Newland’s octaves,
|
A |
B |
C |
D |
E |
F |
G |
|
H |
I |
J |
K |
L |
M |
N |
The pair of elements with similar properties:
A) H and B
B) K and D
C) C and D
D) M and G
8. The anomalous pair of elements in the Mendeleev’s periodic table:
A) Li and K
B) B and Si
C) Co and Ni
D) S and O
9. The elements whose properties were predicted by Mendeleeff even before they were discovered:
A) Scandium
B) Gallium
C) Germanium
D) all of the above
10. Identify the correct match:
A) eka Boron – Scandium
B) eka Aluminium – Germanium
C) eka Silicon – Gallium
D) None of the above
11. Mendeleeff classified the elements into:
A) group of elements with same valency
B) groups and periods
C) group of elements with similar properties
D) all of the above
12. A drawback of Mendeleeff’s periodic table:
A) the elements are arranged in a tabular form
B) elements with similar properties grouped together
C) isotopes were not placed in the periodic table
D) left spaces for undiscovered elements
13. Moseley arranged the elements -
A) into groups and periods
B) in the increasing order of atomic number
C) the properties of the elements belong to a particular group have similar properties
D) all of the above
14. The number of electron shells present in the atom of an element which belongs to 3rd period of The Modern periodic table:
A) 1
B) 2
C) 3
D) 0
15. Which of the followings is correct combination to represent a group in the Modern periodic table?
A) Group 11 – IA
B) Group 12 – IIA
C) Group 3 – IIIA
D) Group 14 – IVA
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