Limitations of Mendeleev’s Periodic Table

Q.

How many elements did Mendeleevs periodic table contain?

Q. The position of hydrogen could not be justified by Mendeleev.

1. True
2. False

Q.

Which elements were added to the Mendeleevs periodic table later and what was the group number?

Q. $C{l}^{35}$ and $C{l}^{37}$ are not different in their chemical properties because

1. they have different mass number
2. they have different number of electrons
3. they have different number of protons
4. they have the same number of electrons

Q.

According to Mendeleev’s Periodic Law, the elements were arranged in the periodic table in the order of:

1. increasing atomic number

2. decreasing atomic number

3. increasing atomic masses

4. decreasing atomic masses

Q. In Mendeleev's periodic table, some elements with higher atomic masses were placed before the elements with lower atomic masses.

1. False
2. True

Q.

In revised Mendeleevs periodic table, how many elements are there in seventh period?

Q.

How many elements were known at the time of Mendeleev?

1. 118

2. 40

3. 112

4. 63

Q.

Choose the correct alternative from the following:

Which among the following is not an anomalous pair in Mendeleev’s periodic table?

1. Co, Ni

2. Te, I

3. Ar, K

4. Sc, Ga

Q.

State the names of elements whose existence was predicted by Mendeleev.

Q. Reason(s) for the anomalous position of hydrogen in Mendeleev’s periodic table
is/are

1. NaH can be formed similar to NaCl.
2. $H_{2}O$ can be formed similar to $N{a}_{2}O$.
3. Hydrogen exists as a diatomic molecule similar to that of chlorine.
4. All of these

Q.

Which element was placed before iodine in Mendeleev periodic table is.

1. Scandium

2. vanadium

3. Tellurium

4. polonium

Q. The position of hydrogen could not be justified by Mendeleev.

1. True
2. False

Q. Mendeleev arranged isotopes in horizontal rows in his periodic table.

1. True
2. False

Q.

Select the limitations of Mendeleev's periodic table from the given options.

1. Some elements with different properties were kept in the same group.
2. The position of hydrogen was not fixed.
3. The arrangement of elements on the basis of increasing atomic masses was not always followed.
4. Empty spaces were left in case some new elements were discovered.

Q. What were the limitations of Mendeleev's periodic table?

1. Position of hydrogen
2. Position of isotopes
3. Similar elements placed separately
   
4. Blank spaces for undiscovered elements

Q. Which of the following is not a limitation of Mendeléev’s periodic table?

1. Elements of lesser atomic weight were placed before the elements of higher atomic weight
2. Position of isotopes was not fixed in the periodic table
3. Position of hydrogen is not fixed
4. Placement of similar elements at different positions and dissimilar elements at same positions

Q. In Mendeleev's periodic table, some elements with higher atomic masses were placed before the elements with lower atomic masses.

1. False
2. True

Q.

Differentiate between Modern periodic law and Mendeleevs periodic law

Q. Which of the following is not a limitation of Mendeléev's periodic table?

1. Position of isotopes was not mentioned.
2. Dissimilar elements were placed together
3. Elements of group VIII were arranged in three triads but no fixed position was allotted to them
4. Prediction of new elements was done