Chemistry

Chemical Bonding and Molecular Structure

1,277 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

Multiple choice chemistry group 17 group 17 - physical properties physical properties of group 17 elements group 17 elements: the halogen family

Which of the following does not truly represent the property indicated against it?

  1. $ Br _2 < Cl _2 < F _2 $ : Oxidising power
  2. $ Br < Cl < F $ : Electronegativity
  3. $ Br < F < Cl $ : Electron affinity
  4. $ Br _2 < Cl _2 < F _2 $ : Bond energy
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
The correct arrangements along with properties are written against them.

$ Br _2 < Cl _2 < F _2 $ : Oxidising power

$ Br < Cl < F $ : Electronegativity

$ Br < F < Cl $ : Electron affinity

$ F _2 < Br _2 < Cl _2 $ : Bond energy

Thus,we see that the order of bond energy is incorrect in the question. The correct order is given above. 

Hence, option D is correct.
Multiple choice chemistry group 17 group 17 - physical properties physical properties of group 17 elements group 17 elements: the halogen family

Least melting point is shown by the compound-

  1. $PbCl _2$
  2. $SnCl _4$
  3. $NaCl$
  4. $AlCl _3$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

We know that greater the molecular size is; greater will be van der Waal force of attraction between then and higher will be its melting point.

Among given species since in $AlCl _3$; Al has the least size so the van der Waal force of attraction will be least and the melting point of it is lowest. But because of a molecular crystalline structure of $SnCl _4$, it has least melting point among given species.

Multiple choice chemistry group 17 group 17 - physical properties physical properties of group 17 elements group 17 elements: the halogen family

The bond energies of $F _{2}, Cl _{2}, Br _{2}$, and $I _{2}$ are 155 kJ $mol^{-1}, \ $244 kJ $mol^{-1}$, 193 kJ $mol^{-1}$ and 151 kJ $mol^{-1}$ respectively. The weakest bond will be in:

  1. $Br _{2}$
  2. $Cl _{2}$
  3. $F _{2}$
  4. $I _{2}$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Since the bond energy of $I _2$ is least, it's bond will be weakest.

Multiple choice chemistry group 17 group 17 - physical properties physical properties of group 17 elements group 17 elements: the halogen family

The compound IF$ 7$ is named as ________.

  1. iodine heptafluorine

  2. iodine septafluoride

  3. iodine fluoride

  4. none of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

$IF _7$ is named as Iodine (VII) Flouride. Because the halogen of larger size give electron pair and the halogen of small size which has high electronegativity accepts a lone pair of electrons. So suffix '-ide' is added to halogen of small size.

Multiple choice chemistry mix and separate different types of solutions various mixtures introduction to solutions

Dissolution of ionic solid in water is possible when:

  1. $H$ lattice $> H$ hydration
  2. $H$ lattice $= H$ hydration
  3. $H$ hydration $: H$ lattice = 2:1
  4. $H$ hydration $> H$ lattice
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Solution:- (D) ${H} _{\text{hydration}} > {H} _{\text{lattice}}$

In order to dissolve an ionic solid, water molecules must break up the interactions between all of the ions in the solid. The heat of hydration $\left( {H} _{\text{hydration}} \right)$ offsets the lattice energy $\left( {H} _{\text{lattice}} \right)$ of an ionic solid to allow for solution formation to occur typically when ${H} _{\text{hydration}} > {H} _{\text{lattice}}$.

Multiple choice chemistry p- block elements-i study of aluminium chloride study of aluminium structure of some compounds

The molecule which is NOT hydrolysed by water at $25^oC$ is

  1. $AICI _3$
  2. $SiCI _4$
  3. $BF _3$
  4. $SF _6$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Silicon tetrachloride, boron trifluoride, and aluminium chloride all readily undergo hydrolysis due to vacant d-orbitals or electron deficiency allowing water molecules to coordinate. Sulfur hexafluoride is sterically hindered and lacks accessible coordination sites, making it inert to water at room temperature.

Multiple choice chemistry p- block elements-i study of aluminium chloride study of aluminium structure of some compounds

Aluminium (III) chloride forms a dimer because aluminium :

  1. cannot form a trimer.

  2. has high ionization energy.

  3. belongs to third group.

  4. can have higher coordination number.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

 Aluminium trichloride is a dimer, $Al _2Cl _6$.

This is because: 
$AlCl _3$ forms a dimer as there is unsaturation in coordination. Also it enables Al atoms to complete their octets.

Aluminium is more like a metalloid than a metal.The electronegativity of aluminium is higher than the electronegativity of sodium .


Multiple choice chemistry p- block elements-i study of aluminium chloride study of aluminium structure of some compounds

Which of the following is a Lewis acid?

  1. $AlCl _3$
  2. $MgCl _2$
  3. $CaCl _2$
  4. $BaCl _2$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
$Al$ needs two more electrons to complete its octet, it has the tendency to accept a pair of electrons to achieve stable electronic configuration. By definition, those which accepts electrons are called lewis acids. 

Thus, $Al{Cl} _{3}$ is a Lewis acid.


Hence, the correct answer is option $\text{A}$.

Multiple choice chemistry environmental chemistry biochemistry and the environment green chemistry strategies to control environmental pollution and green chemistry

Which of the following compounds are toxic?

  1. Benzene

  2. Toluene

  3. Carbon tetrachloride

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A toxic substance is a substance that can be poisonous or cause health effects.

Benzene is known to cause cancer, based on evidence from studies in both people and lab animals.Basically it is carcinogenic.
Toluene is irritating to the skin, eyes, and respiratory tract. It can cause systemic toxicity by ingestion or inhalation and is slowly absorbed through the skin.
Carbon tetrachloride is one of the most potent hepatotoxins (toxic to the liver), so much so that is widely used in scientific research to evaluate hepatoprotective agents.Exposure to high concentrations of carbon tetrachloride (including vapour) can affect the central nervous system, degenerate the liver and kidneys and prolonged exposure may lead to coma or death.

Multiple choice chemistry introduction to acid and base neutralisations in everyday life acids and bases in daily life neutralisation reaction

Which base is employed as the electrolyte in alkaline batteries?

  1. $Ca(OH) _2$
  2. $Al(OH) _3$
  3. $FeOH$
  4. $KOH$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Aqueous potassium hydroxide is employed as the electrolyte in alkaline batteries based on nickel-cadmium, nickel-hydrogen, and manganese dioxide-zinc. Potassium hydroxide is preferred over sodium hydroxide because its solutions are more conductive.

Multiple choice chemistry the periodic table dobereiner's triads development of the modern periodic table into the history

If the two members of a Dobereiner's triad are chlorine and iodine, then the third member of this triad is :

  1. fluorine

  2. bromine

  3. sodium

  4. calcium
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

According to Dobereiner, the atomic mass of the middle element is nearly equal to the arithmetic mean of the other two. Therefore, the atomic mass of the third element is $=$ $\dfrac{{35.5}+{127}}{2}$ $=$ 81.25, which is the atomic mass of bromine.