Chemistry
Chemical Bonding and Molecular Structure
1,420 Questions
This section tests your knowledge of chemical bonding, molecular structure, and hybridization. It covers ionic and covalent bonds, octet rule exceptions, and molecular geometry. These chemistry questions are common in various competitive entrance examinations.
Ionic and covalent bondsHybridisation of elementsOctet rule exceptionsMolecular geometryIntermolecular forces
Chemical Bonding and Molecular Structure Questions
B
Correct answer
Explanation
Potassium's chemical symbol is K, derived from its Latin name 'Kalium'. The symbol P represents Phosphorus, a completely different element. Chemical symbols often come from Latin or Greek names rather than English.
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Pentaerythritol tetranitrate
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Powdered Explosive TNT
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Pentoerythritol tetranitramine
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Pentaerythrital tetranitramine
A
Correct answer
Explanation
PETN is a high-brisance explosive meaning it creates a powerful shattering effect. The full chemical name is Pentaerythritol Tetranitrate. Options C and D have spelling errors ('pentoerythrital', 'tetranitramine'). Option B is incorrect - PETN and TNT are different explosives.
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cesium
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californium
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nobium
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anthracene
B
Correct answer
Explanation
Californium is considered the most expensive substance in the world, costing approximately $27 million per gram. It is a radioactive element with very limited production and specialized applications in nuclear reactors and detectors. Cesium, niobium, and anthracene are much more common and less expensive.
B
Correct answer
Explanation
Ice is solid water, so its chemical formula remains H2O (two hydrogen atoms bonded to one oxygen atom). Freezing water doesn't change its chemical composition, only its physical state. N2O is nitrous oxide and NO2 is nitrogen dioxide.
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catechol
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hydroquinone
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resorcinol
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All of the above
D
Correct answer
Explanation
The formula C6H6OH is chemically ambiguous/imprecise notation. However, looking at the options: catechol (benzene-1,2-diol), hydroquinone (benzene-1,4-diol), and resorcinol (benzene-1,3-diol) are all benzene diols with formula C6H6O2 (properly C6H4(OH)2). The notation C6H6OH poorly represents any of these, making the question chemically inaccurate, though D is marked correct.
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Nucleons
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Protons
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Electrons
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Neutrons
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Protons and electrons
C
Correct answer
Explanation
Ions are generated by transfer of electrons.
Cations are positively charged ions formed by the loss of electrons from atoms and anions are negatively charged ions formed when an atom gains electrons.
A
Correct answer
Explanation
Yes, it is correct. AgBr shows both types of defects, i.e. Schottky and Frenkel defects.
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Frenkel defects
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Schottky defects
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Interstitial defects
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Vacancy defects
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None of these
B
Correct answer
Explanation
Yes, it is correct. When cations and anions both are missing from regular sites, the defect is called Schottky defect. In Schottky defects, the number of missing cations is equal to the number of missing anions in order to maintain the electrical neutrality of the ionic compound.
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Schottky defects
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Impurities defects
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Metal excess defects
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Frenkel defects
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None of these
B
Correct answer
Explanation
Yes, it is the correct answer. Defects in ionic compounds because of replacement of ions by the ions of other compound is called impurities defects.
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FeCl2
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SnCl2
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AlCl3
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MgCl2
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None of these
C
Correct answer
Explanation
It is correct. It has the maximum charge, smaller size of cation, larger size of anion. So, least ionic character.
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C22-, O2-, CO, NO
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NO+, C22-, CN-, N2
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CN-, N2 , O22-, CO22-
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N2, O2-, NO+, CO
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None of these
B
Correct answer
Explanation
All have 14 electrons. So, they are isoelectronics.
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One sigma and two pi
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One sigma and one pi
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Two sigma and one pi
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Two sigma and two pi
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None of these
A
Correct answer
Explanation
Carbide ion is C22- and is structured with two carbons with triple bond, i.e. one sigma, two pi.
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O-H....N
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F-H....F
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O-H....O
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O-H....F
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None of these
B
Correct answer
Explanation
Fluorine has the highest electronegativity and thus, has the strongest bond.
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NH3
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H2O
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C+H5
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N+H4
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None of these
D
Correct answer
Explanation
It has an bond angle of 109o 28'. tetrahedral structure, sp3 hybridised.
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SO2
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OH2
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SH2
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NH3
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None of these
C
Correct answer
Explanation
Bond angle of SH2 is 90o, which is the smallest among the following.