RRB Junior Engineer / DMS / CMA 2019 · Question 9 of 3719

Which of the following statements about the modern periodic table is NOT correct?

Chemistry - Periodic Table

Aa. There are seven periods in the periodic table
Bb. Period 1 has only one elementCorrect
Cc. The periodic table is arranged in order of atomic number
Dd. There are 18 groups in the periodic table

Answer: B. b. Period 1 has only one element

Explanation

The statement that is NOT correct is: Period 1 has only one element Period 1 of the periodic table actually has two elements: Hydrogen (H) and Helium (He).

Source: RRB JE 2019 CBT-1 (24-May-2019 Shift-2) — ixambee compilation with answer key and solutions · reliable-secondary

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