Question 2 :
Numbering of groups as 1, 2, ........... 18 was adopted by IUPAC in :
Question 4 :
In Newland's classification, elements are arranged in an increasing order of their:
Question 7 :
The three elements A, B and C with similar properties have atomic masses X, Y and Z respectively. The mass of Y is approximately equal to the average mass of X and Z. Such an arrangement of elements called as :<br/>
Question 8 :
Cl, Br, I follows Dobereiner's triads, the atomic masses of Cl and I are 35.5 and 127 respectively. The atomic mass of Br is : <br/>
Question 9 :
Which among the following is not an anomalous pair in Mendeleev's periodic table?
Question 10 :
The number of elements known in Mendeleev's presented periodic table is:<br/>
Question 11 :
In Newlands' table, which of the following elements was not placed in the same group in which cobalt and nickel were present?
Question 12 :
Assertion: The placement of isotopes in Mendeleev's periodic table overcome in the modern periodic table.
Reason: In modern periodic table, the elements have been allotted places based on their atomic numbers
Question 13 :
According to Mendeleev's periodic law, the properties of elements are a periodic function of:<br/>
Question 15 :
Which of the following is the correct set of elements to Dobereiner's triads ?
Question 16 :
The most important active step in the development of periodic table was taken by
Question 18 :
The law used by Newlands to arrange elements is known as <span>Newlands Law of Octave</span> .<br/>
Question 19 :
The groups from $1^{st}$ to $7^{th}$ of Mendeleev's periodic table were divided into ______ subgroups.
Question 21 :
The placement of elements in the Newlands' table was compared to :
Question 22 :
In Doberenier triads, the atomic weights of the elements in a triad are in increasing order.<br/>
Question 23 :
If the two members of a Dobereiner triad are phosphorus and antimony, the third member of this triad is :<br/>
Question 24 :
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).
Question 25 :
The law of triad is applicable to a group of :<br/>
Question 29 :
Eka-Boron was the name given by Mendeleev to the element similar to _______ in properties.
Question 30 :
Assertion: The Newland's law of octaves fail.
Reason: The properties of elements beyond atomic weight 40 cannot be explained.
Question 31 :
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 :
Question 32 :
Which of the following statement about Mendeleev's periodic table is incorrect?
Question 33 :
How many elements were known when Mendeleev presented the periodic table?
Question 34 :
If X and Y are two elements which belong to same group of Newland's periodic table, how many elements exists between X and Y?
Question 36 :
Which of the following sets of atomic masses do not correspond to Dobereiner's triad?<br/>
Question 37 :
Which of the following triads does not follow Dobereiner's law of triads?
Question 38 :
Isotopes could find a position in Mendeleev's periodic table.<br/>State whether the given statement is true or false.<br/>
Question 39 :
The eight group of Mendeleev's periodic table is divided into how many subgroups?
Question 40 :
The element placed with cerium, in the table formed by Newlands' was :
Question 41 :
The name given by Newlands to the arrangement created by him was :
Question 42 :
Whose name is associated with the development of periodic table ?
Question 44 :
Whose name is not associated with the development of periodic Table
Question 45 :
Mendeleev used a Sanskrit numeral before the names of the predicted elements. What was the term used for it?
Question 46 :
The most significant contribution towards the development of periodic table was made by:<br/>
Question 48 :
If the two members of a Dobereiner's triad are chlorine and iodine, then the third member of this triad is :<br/>
Question 49 :
In Mendeleev's periodic table few elements that are chemically similar are placed in the same groups.<br/>
Question 50 :
Which scientist came up with the concept of a periodic table that included all of the known elements?<br>
Question 54 : Which of the following is(are) Dobereiner's triads?<div><br/>(a) P, As, Sb <div>(b) Cu, Ag, Au</div><div><span>(c) Fe, Co, Ni</span></div><div><span>(d) S, Se, Te<br/></span></div></div>
Question 57 : Three elements X, Y and Z form a Dobereiner triad. The ratio of the atomic weight of X to that of Z is 7: 25.<div><br/></div><div> If the sum of the atomic weights of X and Z is 160, find the atomic weights of X, Y and Z.</div>
Question 58 :
Which of the following are the demerits of Mendeleev periodic table?<br/>
Question 60 :
The chemical formula of the oxide of $Eka\ -$ aluminium is:
Question 61 :
Atomic wt. of P is 31 and Sb is 120. What will be the atomic wt. of As, as per Dobernier triad rule?
Question 62 :
When a Dobereiner's triad is considered, the sum of atomic weights of the terminal elements $X$ and $Z$ is 162.5. The atomic weight of $Z$ is 50 units less than 5 times that of $X$. Identify the periods of $X, Y$ and $Z$ respectively in the present periodic table.<br/>
Question 63 : <div><span>Mendeleev predicted the existence of certain elements not known at that time and named two of them as Eka $-$ silicon and Eka $-$ Aluminium.</span><br/></div><div><br/></div>Mention the group of these elements in the Modern Periodic Table :<br/>
Question 64 :
It was assumed by newlands that only 63 elements existed in nature and no more elements would be discovered in the future.
Question 66 :
When Mendeleev started his work , the work , the number of known elements was:
Question 67 :
<span>The standard emf of a galvanic cell involving cell reaction with </span><i>n</i><span> = 2 is found to be 0.295 V at 25C°. The equilibrium constant of the reaction would be</span><br/><span>(Given, </span><span>$F = 96500 C mol^{-1}, R = 8. 314 JK^{-1} mol^{-1}$ )</span>
Question 68 :
Doberiener's system of classification into triads was not found to be useful as he could identify only.
Question 69 :
The Russian chemist Dmitri Mendeleev is generally credited with organizing the chemical elements into a comprehensive periodic table in large part due to the fact that he was able to use his table to predict the existence of elements, like gallium, that were not known at the time $(1872)$, but were discovered later.<br>Which is the best explanation for why Mendeleev was unable to predict the existence of the noble gases (group $18$)?
Question 70 :
According to Mendleev's periodic law which properties of the elements are the periodic function of their atomic masses?
Question 71 :
Dobereiner was the first person to illustrate the relationship between the ____________ of elements and their properties.
Question 72 : <div>Identify the correct sets of entries that are rightly matched.</div><div><br/></div><div> Column A<span> </span>Column B</div><div><br/></div><div>(A) Bridge elements<span> </span>(a) Elements of group IA-VIIA</div><div>(B) Representative elements <span> </span>(b) 2nd-period elements</div><div>(C) Typical elements<span> </span>(c) 7th-period elements</div><div>(D) Transition elements <span> </span>(d) 3rd-period elements</div><div>(E) Transuranic elements<span> </span>(e) Present in 4th, 5th and 6th periods</div>
Question 73 :
The element which resembled cobalt, nickel and was placed in Newland's table far away from those elements was:
Question 75 :
Which of the following sets of elements follows Newland's octave rule?<br/>
Question 76 :
The properties of the elements, as well as the formulae and properties of their compounds depend in a periodic manner on the atomic weights of the elements. This periodic law was given by :
Question 77 :
Mendeleev arranged the known elements in a/an ______ order of their atomic masses.<br/>
Question 78 :
Who was the first to classify the elements into metals and non-metals?
Question 79 :
For which of the pair Newland octave rule is not applicable?
Question 80 :
It was found that the law of octaves was applicable only to :
Question 81 :
Atomic weight of which set of elements were corrected by Mendeleev?
Question 82 :
In Mendeleev's periodic table, gaps were left for the elements to be discovered later. Which of the following elements found a place in the periodic table later?<br>
Question 84 :
In Mendeleev's Periodic Table, gaps were left for the elements to be discovered later. Which of the following elements found a place in the periodic table later?
Question 85 :
The atomic masses of Li and K are 7 and 39, respectively. According to law of triads the atomic mass of Na will be:
Question 86 :
Which of the following is incorrect statement about Mendeleev's classification of elements?
Question 88 :
Chlorine, Y and Iodine form a Dobereiner's triad. Identify the atomic weight of Y.
Question 89 :
The discovery of which of the following group of <span>elements gave a death blow to the Newland's Law?</span>
Question 90 :
If ($N, P, As$) was Dobereiner's triads then what would be the absolute error in atomic mass of phosphorous as compared to the original mass?<br/>Atomic mass : Nitrogen $=14$ amu, Arsenic $=74.9$ amu, Phosphorous $=31$ amu<br/>
Question 92 :
In Mendeleev's periodic table, the gap was not left for one of the following elements. This element is:
Question 95 :
Assertion: Newland's law of octaves of elements is a function of their state that the property of every eighth element is the repetition of the first.
Reason: The maximum of 8 electrons can be accommodated in valence shell.
Question 96 :
The element placed with nickel in the table formed by Newlands was :
Question 98 :
In the modified Mendeleev's periodic table,____ group and____periods are present, whereas in the modern periodic table,____groups and____periods are present, respectively:
Question 99 :
Which of the following statements are correct about Mendeleev's periodic table?<br>i) It is based on increasing order of atomic numbers.<br>ii) Mendeleev corrected the atomic weight of some elements like Be, In etc.<br>iii) $(Ar , H_{2} ), (Co, Cl_{2}), (Te, F_{2})$ are three inverted pairs.<br>iv) It is based on increasing order of atomic weights.
Question 100 :
Which is not anomalous pair of elements in the Mendeleev's periodic table?
