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Multiple choice chemistry the periodic table newland's law of octaves development of the modern periodic table into the history

Dobereiner grouped the elements into triads and Newland gave the:

  1. law of Octaves

  2. mass number

  3. atomic number

  4. valency
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In 1864 newlands in chemistry, the generalization made by the English chemist J.A.R. Newlands in 1865 that, if the chemical elements are arranged according to increasing atomic weight, those with similar physical and chemical properties occur after each interval of seven elements. Newlands was one of the first to detect a periodic pattern in the properties of the elements and anticipated later developments of the periodic law. Hence called law of octaves.

Multiple choice chemistry the periodic table newland's law of octaves development of the modern periodic table into the history

The discovery of which of the following group of elements gave a death blow to the Newland's Law?

  1. Inert gases

  2. Alkali metals

  3. Transuranic element

  4. Halogens
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The discovery of zero group of elements (inert gases) gave a death blow to the Newland's Law.
According to Newlands Law of octaves, when the elements are arranged in the increasing order of atomic weights, the properties of every eighth element are similar to the first one.


Hence, the correct option is $\text{A}$

Multiple choice chemistry the periodic table newland's law of octaves development of the modern periodic table into the history

Which of the following pairs of elements do not follow octave rule?

  1. $Be, B$
  2. $Ca, Sr$
  3. $F, Cl$
  4. $O, S$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The octet rule in chemistry refers to the tendency of atoms to prefer to have eight electrons in the valence shell. Beryllium (Be) and Boron (B) are electron-deficient elements that often form compounds with fewer than eight valence electrons, thus failing to follow the octet rule.

Multiple choice chemistry the periodic table newland's law of octaves development of the modern periodic table into the history

X and Y are two elements having similar properties which obey Newlands law of octaves. The number of elements in between X and Y respectively are:

  1. 8

  2. 6

  3. 7

  4. 9
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Newlands' law of octaves states that every eighth element has properties similar to the first. If X is the first element, the eighth element is Y. The number of elements between them is 8 - 1 - 1 = 6.

Multiple choice chemistry the periodic table newland's law of octaves development of the modern periodic table into the history

The Newland's law of octaves for the classification of elements was found to be applicable only up to the element ______________________.

  1. potassium

  2. calcium

  3. cobalt

  4. phosphorous
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The Newland's law of octaves for the classification of elements was found to be applicable only up to the element calcium.


Law of octaves, in chemistry, the generalization made by the English chemist J.A.R. Newlands in 1865 that, if the chemical elements are arranged according to increasing atomic weight, those with similar physical and chemical properties occur after each interval of seven elements.

 Newlands was one of the first to detect a periodic pattern in the properties of the elements and anticipated later developments of the periodic law.

Multiple choice chemistry the periodic table newland's law of octaves development of the modern periodic table into the history

The elements $A$ and $B$ obey Newland's law of octave. How many elements are there between $A$ and $B$?

  1. 7

  2. 8

  3. 5

  4. 6
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

According to the law of octaves, those with similar physical and chemical properties occur after each interval of seven. 


Thus if $A$ is the first element and $B$ is the eighth element, the number of elements in between $A$ and $B$ is 6.

Hence, option D is correct.