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 chemistry of non-metals oxides of elements simple oxides oxygen

The type of ions responsible for scum formation are:

  1. oxides

  2. hydroxides

  3. chlorides

  4. carbonates
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The scum is formed when soap is used in hard water and hard water consists of carbonate. For this process $Oxides$ ions responsible for scum formation.

Hence,
The option $(A)$ is correct.

Multiple choice chemistry chemistry of non-metals oxides of elements simple oxides oxygen

Which of the following compounds is amphoteric?

  1. $Cr{(OH)} _{2}$
  2. $Fe{(OH)} _{2}$
  3. $Cr{(OH)} _{3}$
  4. $Fe{(OH)} _{3}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

$ Cr(OH) _3$ reacts with bases (hydroxide ions) to give $ [Cr(OH) _6]^{3-}$. It also reacts with acids (hydrogen ions) to give $ [Cr(H _2O) _6]^{3+}$ 


Hence,it act as amphoteric dissolve in both acid and base.

Thus,option C is correct.

Multiple choice bio-chemistry carbohydrate metabolism energy output living organisms and energy production respiration in cell

$\sim P$ in ATP represents

  1. Two bonds with high energy

  2. Two moles of phosphorus

  3. Three atoms of high energy phosphate

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
ATP is known as energy currency of the cell and it is a nucleotide formed by the combination of adenine as a nitrogenous base, ribose sugar, and triphosphate. It is found in free cells which breaks to form energy by breaking it's high energy phosphate bonds. The high energy phosphate bonds break to form ADP and AMP. It is a hydrolysis reaction which occurs at extreme pH. It dephosphorylates to provide energy for metabolic function.
ATP has three phosphate out of which one is directly attached to the ribose with phosphate ester bond and it is low energy bond. The bond between two phosphate groups is a phosphoanhydride bond which is considered as high energy bond. So ATP has only two high energy bond phosphoanhydride bond.
So, the correct answer is option A.
Multiple choice chemistry preparation of gases nitrogen gas component of air - nitrogen nitrogen

Among the following compounds, which on heating do not produce ${ N } _{ 2 }$?

  1. ${ \left( { NH } _{ 4 } \right) } _{ 2 }{ Cr } _{ 2 }{ O } _{ 7 }$
  2. ${ NH } _{ 4 }CI+Na{ NO } _{ 2 }$
  3. ${ NH } _{ 4 }CI+CaO$
  4. $Ba{ \left( { N } _{ 3 } \right) } _{ 2 }$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The reaction is given by,

$2 NH _4Cl + CaO → 2 NH _3 + CaCl _2 + H _2O$

Multiple choice chemistry preparation of gases nitrogen gas component of air - nitrogen nitrogen

Which of the following compound does not liberate nitrogen with $HNO _{2}$?

  1. Carbamide

  2. Primary amine

  3. Secondary amine

  4. Alkanamide
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Secondary amines do not read with $HNO _2$ to produce $H _2.$

$\Rightarrow R _2NH+H-O-N=0\rightarrow R _2N-N=0+H _2O$
Hence, the answer is secondary amines.

Multiple choice chemistry preparation of gases nitrogen gas component of air - nitrogen nitrogen

Which of the following compounds does not give nitrogen on heating?

  1. $NaN _3$
  2. $(NH _4) _2SO _4$
  3. $NH _4NO _2$
  4. $(NH _4) _2Cr _2O _7$.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

(A) $2NaN _3\xrightarrow {\Delta} 2Na+2N _2$
(B) $(NH _4) _2SO _4\xrightarrow {\Delta} 2NH _3+H _2SO _4$
(C) $NH _4NO _2\xrightarrow {\Delta} N _2+2H _2O$
(D) $(NH _4) _2Cr _2O _7\rightarrow N _2+Cr _2O _3+4H _2O$

Multiple choice chemistry preparation of gases nitrogen gas component of air - nitrogen nitrogen

Among the following compounds, which on heating do not produce ${N _2}$?

  1. (${NH _4}) _2 Cr _2 O _7$
  2. ${NH _4 Cl +Na NO _2}$
  3. ${NH _4 Cl+Ca O}$
  4. ${Ba(N _3) _2}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

(NH$ _4$)$ _2$Cr$ _2$O$ _7$ $\rightarrow$ N$ _2$ + Cr$ _2$O$ _3$ + H$ _2$O

NH$ _4$Cl + NaNO$ _2$ $\rightarrow$ N$ _2$ + H$ _2$O + NaCl

2 NH$ _4$Cl + CaO $\rightarrow$ 2 NH$ _3$ + CaCl$ _2$ + H$ _2$O

Ba(N$ _3$)$ _2$ $\xrightarrow{\text{heat}}$ Ba + 3N$ _2$

Thus, 2 NH$ _4$Cl + CaO will not produce N$ _2$.

Hence, the correct option is $\text{C}$
Multiple choice chemistry preparation of gases nitrogen gas component of air - nitrogen nitrogen

Which of the following compounds does not give $N _2$ when heated?

  1. $NH _4NO _2$
  2. $NH _4NO _3$
  3. $NaN _3$

  4. Both A and B
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

$(1)NH _4NO _2\overset{\Delta }{\rightarrow}N _2+2H _2O$
$(2)NH _4NO _3\overset{\Delta }{\rightarrow}N _2O+2H _2O$
$(3)2NaN _3\overset{\Delta }{\rightarrow}3N _2+2Na$

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Which of the following is non-malleable?

  1. Sulphur

  2. Chlorine

  3. Xenon

  4. None of the above
Reveal answer Fill a bubble to check yourself
A,B,C Correct answer
Explanation

Sulphur, chlorine and xenon, all are $p-$block elements.

Element I.e sulphur, chlorine, and xenon posses properties of non-metal like a poor conductor of heat and electricity,  electrons are not free to move, exist in the gaseous state.We know that non-metal are non-malleable. 


Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Which of the following is not malleable?

  1. Sulphur

  2. Selenium

  3. Phosphorus

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

Non-metals are not malleable. They are brittle and hence they break easily. Such non-metals cannot be deformed by a hammer or rolling. Hence, non-metals cannot be deformed to form thin sheets.

Multiple choice commercial applications global environmental change causes of resource depletion causes of greenhouse effect ozone layer depletion

Which type of electron is present in free radical?

  1. Unpaired and extremely reactive

  2. Paired and extremely inactive

  3. Unpaired and extremely inactive

  4. Paired and extremely reactive
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Free radicals have unpaired electrons. These are extremely reactive. As one chlorine free radical can remove 11000 ozone molecules from stratosphere.

Multiple choice commercial applications global environmental change causes of resource depletion causes of greenhouse effect ozone layer depletion

Which chemical is a 'ozone' depleting solvent?

  1. PAN

  2. CFCs

  3. Carbon tetrachloride

  4. Nitrogen
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Carbon tetrachloride (CCl4) is a well-known ozone-depleting substance historically used as a solvent in industrial and laboratory applications. While CFCs are also ozone-depleting, the question specifically asks for a solvent.

Multiple choice commercial applications global environmental change causes of resource depletion causes of greenhouse effect ozone layer depletion

The Hydrochlorofluorocarbons (HCFCs) are the compounds which have the following molecules:HydrogenCarbonChlorineFluorineWhich among the above plays the most important role in Ozone depletion?

  1. Hydrogen

  2. Carbon

  3. Chlorine

  4. Flourine
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In HCFCs, the chlorine atom is the primary agent that is released in the stratosphere and participates in the catalytic cycle that destroys ozone molecules.

Multiple choice chemistry nitrogen and sulfur ammonia-properties and uses ammonia compounds of nitrogen - ammonia

Ammonia is a Lewis base. It forms complexes with cations. Which one of the following cations does not form complex with ammonia?

  1. Ag$^{+}$
  2. Cu$^{2+}$
  3. Cd$^{2+}$
  4. Pb$^{2+}$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Ammonia is a Lewis base. It forms complexes with cations of transition elements. $Pb^{2+}$ does not form a complex with ammonia as lead ($Pb$) is not a transition element. Lead ($Pb$) is a p - block element.

Hence option D is correct.