Why did you need two or more clues to place other elements? Explain using examples.

The study of chemicals is called chemistry.

The answer is mentioned below.

A new element is placed in a periodic table according to the number of electrons present in the atoms or we can say that the new element is placed according to the atomic number.

Hence, these are the following by which a new element is placed in the table,

Hence, the correct answer is atomic number and its mass.

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Two or more clues are required to place elements in the periodic table because different elements have some similar properties.

For example: If it is required to place Chlorine in the periodic table. Its property such as it is a nonmetals is not enough to place it in the periodic table as there are many other nonmetals. So, some more information such as its atomic number is 17 and belongs to 17 group would help more.