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Multiple choice 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

Eka-aluminum and Eka-silicon are known as:

  1. gallium and germanium

  2. aluminium and silicon

  3. iron and sulphur

  4. sodium and silicon
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Answer A

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

Multiple choice 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

The Mendeleev's periodic table consists of groups: 

  1. seven

  2. eight

  3. nine

  4. ten
Reveal answer Fill a bubble to check yourself
B Correct answer
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.
Multiple choice 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

Which element was named Eka-aluminium by Mendeleev?

  1. Scandium

  2. Gallium

  3. Germanium

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

Mendeleev predicted the existence of several elements, naming them based on their position relative to known elements. Eka-aluminium was his name for the element that would later be discovered as Gallium.

Multiple choice 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

The basis of periodic law presented by Mendeleev was: 

  1. valency

  2. atomic mass

  3. atomic number

  4. atomic volume
Reveal answer Fill a bubble to check yourself
B Correct answer
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.

Multiple choice 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

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

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
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.

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

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

  1. mass number

  2. atomic number

  3. atomic weight

  4. all of these
Reveal answer Fill a bubble to check yourself
C Correct answer
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.

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

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

  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
Reveal answer Fill a bubble to check yourself
A Correct answer
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 $A$.

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

The first attempt to classify elements systemically was made by :

  1. Mendeleev

  2. Newland

  3. Lother Meyer

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