Mendeleev's Classification Process

Q.

What is the meaning of periodic function in Mendeleev's periodic law?

Q. The elements in the Mendeleev’s periodic table were arranged in the increasing order of their atomic masses. But, the sequence was inverted so that two elements with similar properties could be grouped together. Identify those two elements.

1. Lithium (Li) and Sodium (Na)
2. Beryllium (Be) and Magnesium (Mg)
3. Potassium (K) and Calcium (Ca)
4. Cobalt (Co) and Nickel (Ni)

Q.

Which law states that the properties of the elements are a periodic function of their atomic masses?

1. Modern periodic law

2. Dobereiner's Law

3. Mendeleev's Periodic Law

4. Newland's Law

Q.

(a) What was Mendeleev's basis for classification of elements ?

(b) Mendeleev's contributions to the concept of periodic table laid the foundation for the Modern Periodic Table.Give reasons.

Q.

Mendeleev gave prefix ‘Eka’ (one) to the name of the preceding element for the undiscovered elements in the group. What do the names, Eka-aluminium and Eka-silicon represent according to Mendeleev?

1. Germanium and Gallium

2. Scandium and Gallium

3. Gallium and Germanium

4. Boron and Carbon

Q.

Mendeleev's contributions to the concept of the periodic table laid the foundation for the Modern Periodic Table.

Give reasons

Q. On what conditions or by comparing what conditions does Mendeleev was able to predict the properties for the undiscovered element and left the gap for them

Q.

In Mendeleev’s periodic table, the vertical columns are called _i____________ and the horizontal rows are called ii_______.

1. 

2. 

3. 

4. 

Q.

Give a one-word answer.

The scientist who left gaps in his periodic table.

Q. Assertion :According to Mendeleev, periodic properties of elements are periodic function of their atomic number. Reason: Atomic number is equal to the number of protons.

1. Both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
2. Both Assertion and Reason are correct, but Reason is not the correct explanation of assertion.
3. Assertion is correct but Reason is incorrect.
4. Assertion is incorrect but Reason is correct.

Q. How many elements were known at the time of Mendeleevs classification of elements?

Q.

How many elements did Mendeleev's periodic table contain?

1. 17

2. 58

3. 118

4. 63

Q.

In Mendeleev’s periodic table, all the elements are sorted by the periodic functions of their ___ .

1. 2 elements

2. 3 elements

3. 4 elements

4. 5 elements

Q. What physical and chemical properties of elements were used by Mendeleev in creating his periodic table? List two observations which posed a challenge to Mendeleev's Periodic Law.

Q. The elements in the Mendeleev’s periodic table were arranged in the increasing order of their atomic masses. But, the sequence was inverted so that two elements with similar properties could be grouped together. Identify those two elements.

1. Cobalt (Co) and Nickel (Ni)
2. Lithium (Li) and Sodium (Na)
3. Beryllium (Be) and Magnesium (Mg)
4. Potassium (K) and Calcium (Ca)

Q. Which of the following statement is correct in regard to the classification of elements?

(a) Elements in modern periodic table are arranged on the basis of increasing atomic masses.
(b) Elements in Mendeleev's periodic table are arranged on the basis of increasing atomic numbers.
(c) In modern periodic table, the element nickel of lower atomic mass is kept before the element cobalt of higher atomic mass.
(d) In modern periodic table, the isotopes of chlorine having different atomic masses are kept in the same group.

Q.

With respect to the merits of the Mendeleev periodic table answer the following question.

Why did he leave gaps in his periodic table?

Q. Name the three classes in which elements are classified. Which was the first metal used by man?

Q. Question 3
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?

(a) Germanium
(b) Chlorine
(c) Oxygen
(d) Silicon

Q. Which two criteria did Mendeleev use to classify the elements in his table?

Q. Two elements were elected by Mendeleev for studying the properties of compounds formed by other elements with the selected elements. What were the selected elements?

1. Hydrogen, Carbon
2. Oxygen, Carbon
3. Oxygen, Nitrogen
4. Hydrogen, Oxygen

Q. Which important property did Mendeleev use to classify the elements in his periodic table ?

Q.

Question 3
What were the criteria used by Mendeleev in creating his periodic table?