Which one of the following statements is incorrect?
Which one of the following statements is incorrect?
Show Hint
- van Arkel method is used to purify tungsten.
- The malleable iron is prepared from cast iron by oxidising impurities in a reverberatory furnace.
- Cast iron is obtained by melting pig iron with scrap iron and coke using hot air blast.
- Boron and Indium can be purified by zone refining method.
The Correct Option is A
Approach Solution - 1
So, the correct answer is (A) : van Arkel method is used to purify tungsten.
Approach Solution -2
- Option (1):Van Arkel method is used to purify titanium, not tungsten. Tungsten is purified by other methods like hydrogen reduction.
- Option (2):The zone refining method is used to purify metals like boron and indium, which have low melting points.
- Option (3): Cast iron is indeed obtained by melting pig iron with scrap iron and coke in a blast furnace.
- Option (4): Malleable iron is prepared from cast iron by heating it in a reverberatory furnace with the proper oxidation of impurities.
Thus, the incorrect statement is option (1).
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Match List-I with List-II.
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Concepts Used:
Classification of Elements & Periodicity in Properties
Since many elements were being discovered in the 19th century and the study of these elements individually was proving difficult, classification of elements was made necessary.
Classification by Johann Dobereiner - German chemist Johann Dobereiner classified certain elements on the basis of their similar properties in the groups of continuing - three elements each. These groups were called ‘triads’. In every triad, the atomic weight of the middle element was equal to the average of the atomic weights of the first and third elements.
Newlands Law of Octaves - The elements were arranged in increasing order of their atomic weights and found that every 8th element shows similarity with the 1st element.
Mendeleev’s Periodic Table - The arrangement of all 63 elements in rows or columns in order of their atomic weight was made by Mendeleev. He left some space for corresponding elements in his periodic table which were not even discovered till then. Although he predicted the properties of those elements through his periodic classification of elements.
Modern Periodic Law - The properties of the elements of the modern periodic law are periodic functions of their atomic numbers.