Which allotropic form of phosphorous is the most stable ?
Correct answer: B. black
- A. White
- B. black
- C. red
- D. Violet
Explanation
Black phosphorus is the most stable allotrope at ordinary temperature because its layered structure has the lowest energy among the common forms. White phosphorus is more reactive, while red and violet phosphorus are less stable than black phosphorus. The likely trap is red phosphorus because it is safer and more stable than white phosphorus, but black phosphorus is the thermodynamically most stable form.
Last updated
About Periodic Properties and Trends
Periodic properties arise from electron configuration and effective nuclear charge, producing trends in atomic and ionic radius, ionization energy, electron affinity, electronegativity, metallic character and reactivity. Comparisons run across periods and down groups, with attention to common exceptions. The topic also relates these trends to the behavior of s-block and p-block elements.
Practise s-Block and p-Block Elements
1,359 free s-Block and p-Block Elements MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Chemistry questions like this
Chemistry is on 12 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
2. Law of octaves was proposed by
7th period of the periodic table contains normal elements:
(A), (B) and (C) are elements in the third period. The oxide of(A) is ionic, that of (B) is amphoteric and that of (C) is a giant molecule (covalent network). (A), (B) and (C) have atomic numbers in the order:
(A), (B) and (C) are elements in the third short period. Oxide of (A) is ionic, that of (B) is amphoteric and of (C) a giant molecule. (A), (B) and (C) have atomic numbers in the order of:
A gas that reacts with CaO and not with NaHCO3 is: