Advertisements
Advertisements
प्रश्न
In Dobereiner’s triads Li, Na, K, the atomic masses of Lithium and Potassium are 6.9 and 39.1 respectively, then what will be the atomic mass of sodium?
उत्तर
According to Doberiner’s triads, the average atomic mass of two elements is the atomic mass of the third element in a series Na and K.
Average atomic mass of sodium = `"Atomic mass of Li and K"/2`
`= (6.9+39.1)/2`
= `46/2`
= 23
APPEARS IN
संबंधित प्रश्न
Did Dobereiner’s triads also exist in the columns of Newlands’ Octaves? Compare and find out.
The modern periodic table has been evolved through the early attempts of Dobereiner, Newland and Mendeleev. List one advantage and one limitation or all the three attempts.
Name the scientist who gave Law of triads in the early classification of elements.
A, B and C are the elements of a Dobereiner's triad. If the atomic mass of A is 7 and the of C is 39, what should be the atomic mass of B?
State one example of a Dobereiner's triad, showing in it that the atomic mass of middle element is half-way between those of the other two.
What is Debereiner's law of triads? Explain with the help of one example of a Dobereiner's triad.
What were the limitations of Dobereiner's classification of elements?
The three imaginary elements X, Y and Z represent a Dobernener's triad. If the atomic mass of element X is 14 and that of element Y is 46, then the atomic mass of element Z will be:
(a) 28
(b) 60
(c) 78
(d) 72
Can the following groups of elements be classified as Dobereiner's triads?
(a) Na, Si, Cl
(b) Be, Mg, Ca
Give reason for your answer.
(Atomic masses : Be 9 ; Na 23 ; Mg 24 ; Si 28 ; Cl 35.5 ; Ca 40)
In Dobereiner’s triad containing Li, Na, K, if atomic masses of Lithium & Potassium are 6.9 and 39.1, then what will be the atomic mass of Sodium?
What was Dobereiner’s basis, of classification of elements?
State Dobereiner’s Law of Triads with suitable examples.
Explain why Dobereiner’s method of classification of elements did not hold much weightage for future classification.
Dobereiner laid down the _______ rule.
Find the odd one out and give its explanation.
Write the characteristic of Dobereiner’s triads?
According to Dobereiner’s triads rule, three elements in an increasing order of atomic mass shows _______.
Write the name.
The atom having the biggest atomic size from period 2.
In Dobreiner's triads, three elements appear to be arranged in ascending order of their atomic number.
State Dobereiner’s Law of Triads.
If Dobereiner is related with ‘law of triads’, then Newlands is related with ______.
In Dobereiner’s triads, the atomic weight of the middle element is ______ the of the atomic masses of 1st and 3rd elements.
Pick out the chemically most reactive elements from the given triads.
Li, Na, K F, Cl, Br
Can the following groups of elements be classified as Döbereiner's triad?
- Na, Si, Cl
- Be, Mg, Ca
Atomic mass of Be 9; Na 23; Mg 24; Si 28; Cl 35; Ca 40 Explain by giving reason.
