MEDIUM
10th CBSE
IMPORTANT
Earn 100

What do you understand by triad of elements? Give an example.

Important Questions on Periodic Classification Of Elements

MEDIUM
10th CBSE
IMPORTANT
Core Science Chemistry>Chapter 5 - Periodic Classification Of Elements>EXERCISE 5A>Q 2
State Dobereiner’s law of triads.
HARD
10th CBSE
IMPORTANT
Core Science Chemistry>Chapter 5 - Periodic Classification Of Elements>EXERCISE 5A>Q 3
Cl, Li, Ca, Br, Na,Sr, I, K and Ba. From the list of elements given above make three triads and name the family of each triad,
HARD
10th CBSE
IMPORTANT
Core Science Chemistry>Chapter 5 - Periodic Classification Of Elements>EXERCISE 5A>Q 4
Can the following groups of elements be classified as Dobereiner’s triad?

(a) Na, Si, CI
(b) Be, Mg, Ca
Atomic mass of Be 9; Na 23; Mg 24; Si 28; Cl 35; Ca 40

Explain by giving a reason.
HARD
10th CBSE
IMPORTANT
Core Science Chemistry>Chapter 5 - Periodic Classification Of Elements>EXERCISE 5A>Q 5
The three elements A. B and C with similar properties have atomic masses X. Y and Z respectively. The mass of Y is approximately equal to the average mass of X and Z. What is such an arrangement of elements called?
Give one example of such a set of elements.
HARD
10th CBSE
IMPORTANT
Core Science Chemistry>Chapter 5 - Periodic Classification Of Elements>EXERCISE 5A>Q 1
(j) What is the achievement of Dobereiner’s law of triads?

(ii) What were the reasons for rejecting this classification?
HARD
10th CBSE
IMPORTANT
Core Science Chemistry>Chapter 5 - Periodic Classification Of Elements>EXERCISE 5A>Q 2
(i) State the law of octaves,
(ii) Name the scientist who framed the above law.
(iii) Two elements A and B obey the law of octaves. How many elements are in between A and B?
HARD
10th CBSE
IMPORTANT
Core Science Chemistry>Chapter 5 - Periodic Classification Of Elements>EXERCISE 5A>Q 1
(i) State two achievements of the law of octaves.
(ii) What were the reasons for rejecting the law of octaves?
HARD
10th CBSE
IMPORTANT
Core Science Chemistry>Chapter 5 - Periodic Classification Of Elements>EXERCISE 5B>Q 1
A set of alkaline earth metals are: