Tag: into the history

Questions Related to into the history

Mendeleev used a Sanskrit numeral before the names of the predicted elements. What was the term used for it?

chemistry the periodic table mendeleef's periodic table mendeleev's periodic law and its limitations mendeleev's periodic table development of the modern periodic table into the history

  1. Sasi

  2. Eka

  3. Astan

  4. Pancan

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Correct Option: B
Explanation:

A Sanskrit numeral used before the names of the predicted elements was Eka which means one.

The elements having more masses were placed before elements having lower masses in Mendleev's periodic table. Guess the pair of elements (higher mass, lower mass).

chemistry the periodic table mendeleef's periodic table mendeleev's periodic law and its limitations mendeleev's periodic table development of the modern periodic table into the history

  1. Cobalt, Nickel

  2. Vanadium, Chromium

  3. Tellurium, Iodine

  4. All of the above

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Correct Option: D
Explanation:

The elements having more masses were placed before elements having lower masses were cobalt, vanadium, tellurium. Its corresponding elements were nickel, chromium and iodine.

Mendeleev's Periodic Table was published in a _________ in 1872.

chemistry the periodic table mendeleef's periodic table mendeleev's periodic law and its limitations mendeleev's periodic table development of the modern periodic table into the history

  1. German journal 

  2. US journal 

  3. Russian journal 

  4. None of the above

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Correct Option: A
Explanation:

Mendeleev's Periodic Table was published in a German journal in 1872. 

_______ were not given separate place in periodic table.

chemistry the periodic table mendeleef's periodic table mendeleev's periodic law and its limitations mendeleev's periodic table development of the modern periodic table into the history

  1. Alkali metals

  2. Isotopes

  3. Halogens

  4. Non-metals

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Correct Option: B
Explanation:

There were many demerits in the Mendeleevs periodic table like Isotopes had to be given the same position in the periodic table though isotopes of the same elements have different atomic masses.

Isotopes could find a position in Mendeleev's periodic table.

chemistry the periodic table mendeleef's periodic table mendeleev's periodic law and its limitations mendeleev's periodic table development of the modern periodic table into the history

  1. True

  2. False

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Correct Option: B
Explanation:

Mendeleev's periodic table failed because he couldn't tell about the position of isotopes, as he arranged elements on the basis of their increasing atomic mass.

In Mendeleev's periodic table, the elements were arranged in the increasing order of their atomic masses. However, cobalt with atomic mass of 58.93 amu was placed before nickel having an atomic mass of  58.69 amu. Reason for the same is that :

chemistry the periodic table mendeleef's periodic table mendeleev's periodic law and its limitations mendeleev's periodic table development of the modern periodic table into the history

  1. the elements with similar size can be grouped together

  2. the elements with different properties can be grouped together

  3. the elements with similar properties can not be grouped together

  4. the elements with similar properties can be grouped together

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Correct Option: D
Explanation:

According to Mendeleev's classification, the properties of elements are the periodic function of their atomic masses and there is a periodic recurrence of elements with similar physical and chemical properties. 


Noble gas being inert, could be placed in a separate group without disturbing the original order.

Hence the correct option is D.

The element eka-silicon predicted by Mendeleev is :

chemistry the periodic table mendeleef's periodic table mendeleev's periodic law and its limitations mendeleev's periodic table development of the modern periodic table into the history

  1. Ge

  2. Ga

  3. Al

  4. Si

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Correct Option: A
Explanation:

Eka-silicon is germanium, whereas eka-aluminium is gallium. Here germanium has 4 electrons in its outer most shell, hence it shares electron with chlorine, that too with 4. In case of gallium, it has three unpaired electrons in its outer most shell.

How did Mendeleev predict the existence of some yet to be discovered elements in his periodic table?

chemistry the periodic table mendeleef's periodic table mendeleev's periodic law and its limitations mendeleev's periodic table development of the modern periodic table into the history

  1. Gaps

  2. Atomic number

  3. Mass number

  4. None of the above

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Correct Option: A
Explanation:

Professor Dmitri Mendeleev published the first periodic table of the atomic elements in 1869 based on properties which appeared with some regularity as he laid out the elements from lightest to heaviest. When Mendeleev proposed his periodic table, he noted gaps in the table, and predicted that as-of-yet unknown elements existed with properties appropriate to fill those gaps.

Mendeleev arranged the elements in increasing order of their atomic masses and according to their physical properties.

chemistry the periodic table mendeleef's periodic table mendeleev's periodic law and its limitations mendeleev's periodic table development of the modern periodic table into the history

  1. True

  2. False

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Correct Option: B
Explanation:

In 1869, just five years after Newlands put forward his Law of Octaves, a Russian chemist called Dmitri Mendeleev published a periodic table. Mendeleev also arranged the elements known at the time in order of relative atomic mass, but he did some other things that made his table much more successful. Hence he arranged according to atomic masses and their chemical properties.

Noble gases were included in Mendeleev's periodic table in :

chemistry the periodic table mendeleef's periodic table mendeleev's periodic law and its limitations mendeleev's periodic table development of the modern periodic table into the history

  1. 1st group

  2. 7th group

  3. 8th group

  4. none of the above

Show answer
Correct Option: D
Explanation:

In the Mendeleev's periodic table, the noble gases were included in the zeroth group.