Tag: basics of chemical bonding

Questions Related to basics of chemical bonding

Multiple choice chemistry chemical bonding and structure formal charge basics of chemical bonding types of bonds

Effective charge on each oxygen is $-\frac{1}{4}$ in?

  1. $SO _{3}^{2-}$
  2. $SO _{3-}^{4}$
  3. $ClO _{3}^{-}$
  4. $ClO _{4}^{-}$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In the perchlorate ion (ClO4-), there are four equivalent oxygen atoms sharing a single negative charge delocalized over the entire ion, meaning the effective charge on each oxygen atom is -1/4. In sulfite (SO3 2-), the charge per oxygen is -2/3, and in chlorate (ClO3-), it is -1/3.

Multiple choice chemistry chemical bonding and structure formal charge basics of chemical bonding types of bonds

Among ${ KO } _{ 2 },{ AIO } _{ 2 }^{ - },{ BaO } _{ 2 }\ and\ { NO } _{ 2 }^{ + }$, unpaired electron is present in :

  1. ${ NO } _{ 2 }^{ + }\quad and\quad { BaO } _{ 2 }$
  2. ${ KO } _{ 2 }\quad and\quad AI{ O } _{ 2 }^{ - }$
  3. ${ KO } _{ 2 }$ only
  4. $Ba{ O } _{ 2 }$ only
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

This can be done by counting number of valence electrons


$KO _2=1+2\times 6=17$-Odd number of electrons and hence unpaired.


$AlO^{2-} _2=3+2\times 6+1=14$-Even number of electrons and hence paired.

$BaO _2=2+2\times6=14$-Even number of electrons and hence paired.

$NO^{+} _{2}=5+2\times6 -1=16$-Even number of electrons and hence paired.

Hence option C is the correct answer.

Multiple choice chemistry chemical bonding and structure formal charge basics of chemical bonding types of bonds

Which has highest specific charge?

  1. $Na^{+}(mass\ no\ =23)$
  2. $Mg^{2+}(mass\ no\ =24)$
  3. $Al^{+3}(mass\ no\ =27)$
  4. $Si^{+4}(mass\ no\ =28)$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Specific charge in the ratio of charge of ion to its mass.

Specific charge $=\dfrac { e }{ M } $
For ${ Na }^{ + }=\dfrac { e }{ 23 } ,\quad $ for ${ Mg }^{ 2+ }=\dfrac { 2\times e }{ 24 } $
For ${ Al }^{ 3+ }=\dfrac { 3\times e }{ 27 } ,\quad $ for ${ Si }^{ 4+ }=\dfrac { 4\times e }{ 28 } $
In is in the following order,
${ Si }^{ 4+ }>{ Al }^{ 3+ }>{ Mg }^{ 2+ }>{ Na }^{ + }$

Multiple choice chemistry chemical bonding and structure formal charge basics of chemical bonding types of bonds

In bisulphate ion, the formal charge on sulphur atom is:

  1. $+1$
  2. $+2$
  3. $+4$
  4. $+6$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In the bisulphate ion (HSO4-), the sulphur atom is bonded to four oxygen atoms. One oxygen is bonded to hydrogen, and the others are double-bonded or single-bonded with negative charges to satisfy the octet rule, resulting in a formal charge of +2 on the central sulphur atom.

Multiple choice chemistry chemical bonding and structure formal charge basics of chemical bonding types of bonds

Formal charge on nitrogen and oxygen in $NO^- _3$ ion are respectively: 

  1. $0, \dfrac{-1}{3}$
  2. $+1, \dfrac{-1}{3}$
  3. $+1, \dfrac{-2}{3}$
  4. $0, \dfrac{-2}{3}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Formula change is basically a change given to an atom, on assuming that the electrons in a chemical bond are shared equally between the atoms, neglecting theirrelative, $EN.$

$FC=V-N-\cfrac{B}{2}$       $(V=\text{no. of valance electron}\N=\text{No. of non bonding electrons}\B=\text{No. of electrons in covalent bond})$
$FC$ on $N$ in $NO^- _3=0$
$FC$ on $O$ in $NO _3^-=\cfrac{-1}{3}$

Multiple choice chemistry chemical bonding and structure formal charge basics of chemical bonding types of bonds

Formal charge on nitrogen in $NO _{3}^{-}$ ion is

  1. $+1$
  2. $+2$
  3. $+5$
  4. $Zero$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In the nitrate ion (NO3-), the nitrogen atom is at the center bonded to three oxygen atoms. Using the formal charge formula, nitrogen has 5 valence electrons, 0 lone pair electrons, and 8 bonding electrons (4 bonds), resulting in 5 - 0 - 4 = +1.

Multiple choice chemistry chemical bonding and structure formal charge basics of chemical bonding types of bonds

In the cyanide ion the formal negative charge is on:

  1. $C$
  2. $N$
  3. both $C$ and $N$
  4. resonate between $C$ and $N$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In the cyanide ion the formal negative charge resonates between $C$ and $N$. Cyanide ion has resonating structure, $-\overset { \ _ }{ C } \equiv N\longleftrightarrow \overset { \ _ }{ N } \underrightarrow { = } C$