NDA Government Jobs Exams

Which one among the following does not have an allotrope ?
(A) oxygen (B) Sulphur
(C) Nitrogen (D) Carbon

Read Solution (Total 2)

Answer : C
7 years agoHelpfull: Yes(0) No(0)

B Because o,N,C is the same group thats y S is the best option
5 years agoHelpfull: Yes(0) No(1)

NDA Other Question

Which one among the following transitions is associated with the largest change in energy in hydrogen atom
(A) n = 5 to n = 3 (B) n = 2 to n = 1
(C) n = 3 to n = 2 (D) n = 4 to n = 2 Consider the following statements :
1. Diamond is hard and graphite is soft.
2. diamond is soft and graphite is hard.
3. Diamond is a bad conductor but graphite is a good conductor.
4. Diamond is a good conductor but graphite is a bad conductor.
Which of the statements given above is/are correct ?
(A) 1 and 3 (B) 1 only
(C) 2 and 3 (D) 1 and 4