Question

Arrange the following in order of their increasing atomic number \[ A.\ \mathrm{V} \] \[ B.\ \mathrm{Sc} \] \[ C.\ \mathrm{Mn} \] \[ D.\ \mathrm{Ni} \] Choose the correct answer from the options given below:
• \( \mathrm{C < D < A < B} \)
• \( \mathrm{A < B < C < D} \)
• \( \mathrm{B < C < A < D} \)
• \( \mathrm{B < A < C < D} \)

• A. \( \mathrm{C < D < A < B} \)
• B. \( \mathrm{A < B < C < D} \)
• C. \( \mathrm{B < C < A < D} \)
• D. \( \mathrm{B < A < C < D} \)

Hint:

Remember the first transition series order: \[ \mathrm{Sc < Ti < V < Cr < Mn < Fe < Co < Ni < Cu < Zn} \] Atomic number increases from left to right in a period.

Answer 1

The Correct Option is D

Concept: Atomic number is defined as: \[ \boxed{ \text{Number of protons present in the nucleus of an atom} } \] Elements in the periodic table are arranged in increasing order of atomic number. To arrange the given elements correctly, we first determine their atomic numbers.

Step 1: Find the atomic number of Scandium (\(\mathrm{Sc}\)). Scandium has atomic number: \[ \boxed{21} \] Thus: \[ \mathrm{Sc} = 21 \]

Step 2: Find the atomic number of Vanadium (\(\mathrm{V}\)). Vanadium has atomic number: \[ \boxed{23} \] Thus: \[ \mathrm{V} = 23 \]

Step 3: Find the atomic number of Manganese (\(\mathrm{Mn}\)). Manganese has atomic number: \[ \boxed{25} \] Thus: \[ \mathrm{Mn} = 25 \]

Step 4: Find the atomic number of Nickel (\(\mathrm{Ni}\)). Nickel has atomic number: \[ \boxed{28} \] Thus: \[ \mathrm{Ni} = 28 \]

Step 5: Arrange them in increasing order. Now compare: \[ 21 < 23 < 25 < 28 \] Substituting the symbols: \[ \boxed{ \mathrm{Sc < V < Mn < Ni} } \] Using the labels: \[ \boxed{ B < A < C < D } \]

Step 6: Match with the options. The correct option is: \[ \boxed{(4)} \] Additional Understanding: These elements belong to the first transition series. Order in the periodic table: \[ \mathrm{Sc,\ Ti,\ V,\ Cr,\ Mn,\ Fe,\ Co,\ Ni,\ Cu,\ Zn} \] Atomic number increases from left to right across a period. Final Conclusion: The increasing order of atomic number is: \[ \boxed{ B < A < C < D } \] Hence, the correct answer is: \[ \boxed{(4)} \]