Tag: development of the modern periodic table

Questions Related to development of the modern periodic table

Eka-aluminum and Eka-silicon are known as:

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. gallium and germanium

  2. aluminium and silicon

  3. iron and sulphur

  4. sodium and silicon

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Correct Option: A
Explanation:

Answer A

According to Mendeleev he named eka aluminium presently known as Gallium
and eka silicon presently known as Germanium.

The Mendeleev's periodic table consists of groups: 

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. seven

  2. eight

  3. nine

  4. ten

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Correct Option: B
Explanation:
Eight groups were there in the Mendeleev's periodic table.

Mendeleev divided his periodic table in eight groups and seven periods.

Option B is correct.

Which element was named Eka-aluminium by Mendeleev?

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. Scandium

  2. Gallium

  3. Germanium

  4. Indium

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Correct Option: B

The basis of periodic law presented by Mendeleev was: 

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. valency

  2. atomic mass

  3. atomic number

  4. atomic volume

Show answer
Correct Option: B
Explanation:

He grouped the elements with similar properties and observed that elements were arranged in the increasing order of atomic mass and there was the periodic occurrence of elements with similar properties.

According to this observation, he formulated a periodic law which states:

“the properties of elements are the periodic function of their atomic masses.”

Option B is correct.

In Mendeleev's periodic table few elements that are chemically similar are placed in the same groups.

chemistry 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: A
Explanation:

Mendeleev arranged the elements having similar configuration placed in the vertical columns as they will have the same unpaired electrons hence reflecting the similar properties. In Mendeleev's periodic table few elements that are chemically similar are placed in separate groups.

The horizontal rows in Mendleev's table were called :

chemistry 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. groups

  2. rows

  3. periods

  4. none of the above

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Correct Option: C
Explanation:

The horizontal rows in Mendleev's table were called periods. There are seven periods in Mendeleev's periodic table.

The vertical columns in Mendeleev's table were called :

chemistry 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. verticals

  2. periods

  3. columns

  4. groups

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Correct Option: D
Explanation:

The vertical columns in Mendeleev's table were called groups. There are $8$ groups in Mendeleev's periodic table.

In Newland's classification, elements are arranged in an increasing order of their:

chemistry periodic table development of the modern periodic table into the history mendeleef's periodic table

  1. mass number

  2. atomic number

  3. atomic weight

  4. all of these

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Correct Option: C
Explanation:

Newlands arranged elements in increasing order of their atomic weight and stated that every eighth element resembled properties of first element. This is Newland's law of Octaves. Hence correct answer for asked question is option C-atomic weight.

Which of the following is the correct set of elements to Dobereiner's triads ?

chemistry periodic table development of the modern periodic table into the history mendeleef's periodic table

  1. Li - 7, Na - 23, K -39

  2. Br - 80, Cl - 35.5, I - 127

  3. Fe - 55.85, Ni - 58.71, Co - 58.93

  4. All of these

Show answer
Correct Option: A
Explanation:

Dobereiner's triads are a group of three elements in which the atomic mass of the middle element is equal to the average of atomic masses of the first and the third element.


For option A,
Average of atomic masses of first and last elements = $7+ \dfrac{39}{2} = 23$
This is the atomic mass of second element.

For option B.
Average of atomic masses of first and last elements = $80+ \dfrac{127}{2} = 103.5$
This is not the atomic mass of the second element.

For option C,
Average of atomic masses of first and last elements = $55.85+ \dfrac{58.93}{ 22} = 55.89$
This is not the atomic mass of the middle element.

Hence, the correct answer is option $A$.

The first attempt to classify elements systemically was made by :

chemistry classification of elements- the periodic table development of the modern periodic table into the history mendeleef's periodic table

  1. Mendeleev

  2. Newland

  3. Lother Meyer

  4. Dobereiner

Show answer
Correct Option: D
Explanation:

The first attempt to classify elements systemically was made by Dobereiner.
The triads of elements that showed similar chemical properties.
Other properties of the elements followed trends in which the value of the middle element of the triad was in between those of the end members.