Please Wait... While Loading Full Video

Tricks of Periodic Classification of Elements for NDA

Periodic Laws, Mandeleev's Periodic Table and Modern Periodic Law

Q 1744680553

The period number in the long form of the periodic table is equal to
NCERT Exemplar
(A)

magnetic quantum number of any element of the period

(B)

atomic number of any element of the period

(C)

maximum principal quantum number of any element of the period

(D)

maximum azimuthal quantum number of any element of the period

Solution:

Since each period starts with the filling of electrons in a new principal quantum
number, therefore, the period number in the long form of the periodic table refers to the
maximum principal quantum number of any element in the period.
Period number= maximum n of any element (where, n =principal quantum number).
Correct Answer is `=>` (C) maximum principal quantum number of any element of the period
Q 2817845789

Mendeleev corrected the atomic weight of

(A)

Be

(B)

ln

(C)

Os

(D)

All of these

Solution:

Since each period starts with the filling of electrons in a new principal quantum
number, therefore, the period number in the long form of the periodic table refers to the
maximum principal quantum number of any element in the period.
Period number= maximum n of any element (where, n =principal quantum number).
Correct Answer is `=>` (D) All of these
Q 2887145987

Which period and group in the long form of periodic table contain maximum number of elements?

(A)

5th period IInd group

(B)

6th period IIInd group

(C)

6th period IInd group

(D)

1th period IInd group

Solution:

Since each period starts with the filling of electrons in a new principal quantum
number, therefore, the period number in the long form of the periodic table refers to the
maximum principal quantum number of any element in the period.
Period number= maximum n of any element (where, n =principal quantum number).
Correct Answer is `=>` (B) 6th period IIInd group
Q 2817556480

Which of the following sets of elements belong to the same period?

(A)

`He, Ne, Ar`

(B)

`Ni, Cu, Zn`

(C)

`Cl , Br , I`

(D)

`Na, Cu, Mg`

Solution:

Since each period starts with the filling of electrons in a new principal quantum
number, therefore, the period number in the long form of the periodic table refers to the
maximum principal quantum number of any element in the period.
Period number= maximum n of any element (where, n =principal quantum number).
Correct Answer is `=>` (B) `Ni, Cu, Zn`
Q 1714580459

The statement that is not correct for periodic classification of elements is
NCERT Exemplar
(A)

The properties of elements are periodic function of their atomic numbers

(B)

Non-metallic elements are less in number than metallic elements

(C)

For transition elements, the 3d-orbitals are filled with electrons after 3forbitals and before 4s-orbitals

(D)

The first ionisation enthalpies of elements generally increase with increase in atomic number as we go along a period

Solution:

In case of transition elements (or any elements), the order of filling of electrons in various
orbital is `3p < 4s < 3d`. Thus, 3d orbital is filled when 4S orbital gets completely filled.
Correct Answer is `=>` (C) For transition elements, the 3d-orbitals are filled with electrons after 3forbitals and before 4s-orbitals
Q 2847045883

The base of modern periodic table is

(A)

atomic weight

(B)

atomic number

(C)

atomic volume

(D)

atomic energy

Solution:

In case of transition elements (or any elements), the order of filling of electrons in various
orbital is `3p < 4s < 3d`. Thus, 3d orbital is filled when 4S orbital gets completely filled.
Correct Answer is `=>` (B) atomic number

Classification of Elements

Q 1774880756

Which of the following sequences contain atomic numbers of only
representative elements?
NCERT Exemplar

(This question may have multiple correct answers)

(A) 3, 33, 53, 87
(B) 2, 10, 22, 36
(C) 7, 17, 25, 37, 48
(D) 9, 35, 51, 88
Solution:

Elements of s and p-block elements are called representative elements. Elements of d-block
(Z = 21-30; 39-48; 57 and 72-80: 89 and I 04-112) are called transition elements while those
oft-block (with Z 58- 1 and Z = 90-10:3) are called inner transition elements.
With reference to this division. elements listed under option (a) and option (d) are all
representative elements.
Correct Answer is `=>` (A)
Q 2867156085

The block in which metals, metalloids. non-metals and inert gases are all present

(A)

s-block

(B)

p-block

(C)

d-block

(D)

f-block

Solution:

Elements of s and p-block elements are called representative elements. Elements of d-block
(Z = 21-30; 39-48; 57 and 72-80: 89 and I 04-112) are called transition elements while those
oft-block (with Z 58- 1 and Z = 90-10:3) are called inner transition elements.
With reference to this division. elements listed under option (a) and option (d) are all
representative elements.
Correct Answer is `=>` (B) p-block
Q 2847256183

Which of the following groups may contain a metalloid ?

(A)

IA

(B)

IIA

(C)

VIA

(D)

None of these

Solution:

Elements of s and p-block elements are called representative elements. Elements of d-block
(Z = 21-30; 39-48; 57 and 72-80: 89 and I 04-112) are called transition elements while those
oft-block (with Z 58- 1 and Z = 90-10:3) are called inner transition elements.
With reference to this division. elements listed under option (a) and option (d) are all
representative elements.
Correct Answer is `=>` (C) VIA
Q 1724580451

Which of the following is not an actinoid?
NCERT Exemplar
(A)

Curium (Z = 96)

(B)

Californium (Z = 98)

(C)

Uranium (Z = 92)

(D)

Terbium (Z = 65)

Solution:

Elements with atomic number, Z = 90 to 103 are called actinoids. Thus, terbium
(Z = 65) is not an actinoid. Terbium belong to lanthanoids
Correct Answer is `=>` (D) Terbium (Z = 65)
Q 2817356280

Which of the following is known as wonder element ?

(A)

`Zr`

(B)

`Zn`

(C)

`Ti`

(D)

None of these

Solution:

Elements with atomic number, Z = 90 to 103 are called actinoids. Thus, terbium
(Z = 65) is not an actinoid. Terbium belong to lanthanoids
Correct Answer is `=>` (C) `Ti`
Q 2827356281

Element A belongs to group VIIA in p - block and element B belongs to group IA in s-block of the periodic table. Out of the following assumptions, the correct one is

(A)

A and B are metals

(B)

A and B are non - metals

(C)

A is a metal and E is a non-metal

(D)

A is a non-metal and B is a metal

Solution:

Elements with atomic number, Z = 90 to 103 are called actinoids. Thus, terbium
(Z = 65) is not an actinoid. Terbium belong to lanthanoids
Correct Answer is `=>` (D) A is a non-metal and B is a metal
Q 2807756688

In the context of lanthanoids, which of the following statements is not correct'?

(A)

There is a gradual decrease in tile raclii of the members with increasing atomic number in tile series

(B)

All the members exhibit + 3 oxidation stale

(C)

Because of similar properties tile separation of lanthanoids is not easy

(D)

Availability ot 4f-electrons results in the formation of compounds in +4 state for all members of the series

Solution:

Elements with atomic number, Z = 90 to 103 are called actinoids. Thus, terbium
(Z = 65) is not an actinoid. Terbium belong to lanthanoids
Correct Answer is `=>` (D) Availability ot 4f-electrons results in the formation of compounds in +4 state for all members of the series
Q 1764680555

The elements in which electrons are progressively filled in 4f-orbital are called
NCERT Exemplar
(A)

actinoids

(B)

transition elements

(C)

lanthanoids

(D)

halogens

Solution:

The elements in which electrons are progressively filled in 4f-orbital are called
lanthanoids. Lanthanoids consist of elements from Z =58 (cerium) to 71 (lutetium).
Correct Answer is `=>` (C) lanthanoids
Q 2877256186

The element with electronic configuration `3d^5 4s^1` is

(A)

metalloid

(B)

non-metal

(C)

transition metal

(D)

metal

Solution:

The elements in which electrons are progressively filled in 4f-orbital are called
lanthanoids. Lanthanoids consist of elements from Z =58 (cerium) to 71 (lutetium).
Correct Answer is `=>` (C) transition metal
Q 2807256188

In which of the following the tendency towards the formation of coloured ion is maximum?

(A)

s-block elements

(B)

d-block elements

(C)

p-block elements

(D)

All of the above

Solution:

The elements in which electrons are progressively filled in 4f-orbital are called
lanthanoids. Lanthanoids consist of elements from Z =58 (cerium) to 71 (lutetium).
Correct Answer is `=>` (B) d-block elements
Q 2807356288

Which of the following belongs to representative group of elements of periodic table ?

(A)

Lanthanum

(B)

Argon

(C)

Chromium

(D)

Aluminium

Solution:

The elements in which electrons are progressively filled in 4f-orbital are called
lanthanoids. Lanthanoids consist of elements from Z =58 (cerium) to 71 (lutetium).
Correct Answer is `=>` (D) Aluminium

Periodic Properties


Q 2027180081

Match the correct atomic radius with the element.








ElementAtomic radius (pm)
Be 74
C 88
O 111
B 77
N 66

NCERT Exemplar
Solution:

All the given elements are of same period and along a period, atomic radii decreases
because effective nuclear charge increases. Thus, the order of atomic radii is
0 < N < C < B < Be or, Be = 11 pm, 0 = 66 pm, C = 77 pm, B 88 pm, N = 74 pm.
Q 2887556487

Which of the following is most electronegative ?

(A)

Lead

(B)

Silicon

(C)

Carbon

(D)

Tin

Solution:

All the given elements are of same period and along a period, atomic radii decreases
because effective nuclear charge increases. Thus, the order of atomic radii is
0 < N < C < B < Be or, Be = 11 pm, 0 = 66 pm, C = 77 pm, B 88 pm, N = 74 pm.
Correct Answer is `=>` (C) Carbon
Q 2817656580

Which has least ionisation potential ?

(A)

`N`

(B)

`O`

(C)

`F`

(D)

`Ne`

Solution:

All the given elements are of same period and along a period, atomic radii decreases
because effective nuclear charge increases. Thus, the order of atomic radii is
0 < N < C < B < Be or, Be = 11 pm, 0 = 66 pm, C = 77 pm, B 88 pm, N = 74 pm.
Correct Answer is `=>` (B) `O`
Q 1714480359

Consider the iso electronic species, `Na^(+) , Mg^(+2) ,F^(-) text(and) O^(-2)` The correct order of increasing length of their radii is
NCERT Exemplar
(A)

`F < O^(2-) < Mg^(2+) < Na^(+)`

(B)

`Mg^(2+) < Na^(+) < F^- < O^(2-)`

(C)

`O^(2-) < F^(-) < Na^(+) < Mg^(2+)`

(D)

`O^(2-) < F^(-) < Mg^(2+) < Na^(+)`

Solution:

In case of isoelectronic species ionic radii `prop 1/text(atomic number)`

The ionic radii increases as the positive charge decreases or the negative charge
increases

lon `Mg^(2+) < Na^(+) , < F^- < O^(2-)`


Atomic number (12) (11) (9) (8)
Correct Answer is `=>` (B) `Mg^(2+) < Na^(+) < F^- < O^(2-)`
Q 2847656583

Which of the following has the largest ionic radius ?

(A)

`Be^(2+)`

(B)

`Mg^(2 +)`

(C)

`Ca^(2+)`

(D)

`Sr^(2+)`

Solution:

In case of isoelectronic species ionic radii `prop 1/text(atomic number)`

The ionic radii increases as the positive charge decreases or the negative charge
increases

lon `Mg^(2+) < Na^(+) , < F^- < O^(2-)`


Atomic number (12) (11) (9) (8)
Correct Answer is `=>` (D) `Sr^(2+)`
Q 1774180956

Ionic radii vary in
NCERT Exemplar
(A)

inverse proportion to the effective nuclear charge

(B)

inverse proportion to the square of effective nuclear charge

(C)

direct proportion to the screening effect

(D)

direct proportion to the square of screening effect

Solution:

Ionic radius decreases as the effective nuclear charge increases

`text(Ionic radius) prop1/text(etfective nuclear charge)`

Further, ionic radius increases as the screening effect increases.

`text(Ionic radius) proptext( screening effect)`
Correct Answer is `=>` (A)
Q 2867656585

On descending a group , electropositive character of elements

(A)

increases

(B)

decreases

(C)

remains same

(D)

None of these

Solution:

Ionic radius decreases as the effective nuclear charge increases

`text(Ionic radius) prop1/text(etfective nuclear charge)`

Further, ionic radius increases as the screening effect increases.

`text(Ionic radius) proptext( screening effect)`
Correct Answer is `=>` (A) increases
Q 2817656589

Which of the following order of ionisation energy is correct?

(A)

`Be < B < C < N < O`

(B)

`B < Be < C < O < N`

(C)

`Be > B > C > N > O`

(D)

`B < Be < N < C < O`

Solution:

Ionic radius decreases as the effective nuclear charge increases

`text(Ionic radius) prop1/text(etfective nuclear charge)`

Further, ionic radius increases as the screening effect increases.

`text(Ionic radius) proptext( screening effect)`
Correct Answer is `=>` (B) `B < Be < C < O < N`
Q 1724680551

Among halogens, the correct order of amount of energy released in electron gain (electron gain enthalpy) is
NCERT Exemplar
(A)

`F > Cl > Br > I`

(B)

`F < Cl < Br < I`

(C)

`F < Cl > Br > I`

(D)

`F < Cl < Br < I`

Solution:

As we move from Cl to I the electron gain enthalpy (i.e., energy released in electron
gain) become less and less negative due to a corresponding increase in the atomic
size.
However, the electron gain enthalpy of F is less negative than that of Cl due to its small
size. Thus, the negative electron gain enthalpy follows the order


`F < Cl > Br > I`
Correct Answer is `=>` (C) `F < Cl > Br > I`
Q 2827756681

In the following, the dements with the highest electro-positivity is

(A)

copper

(B)

cesium

(C)

barium

(D)

chromium

Solution:

As we move from Cl to I the electron gain enthalpy (i.e., energy released in electron
gain) become less and less negative due to a corresponding increase in the atomic
size.
However, the electron gain enthalpy of F is less negative than that of Cl due to its small
size. Thus, the negative electron gain enthalpy follows the order


`F < Cl > Br > I`
Correct Answer is `=>` (B) cesium
Q 2837756682

In which of the following energy is absorbed ?

(A)

`F -> F^-`

(B)

`Cl -> Cl^-`

(C)

`O -> O^(2-)`

(D)

`H -> H^-`

Solution:

As we move from Cl to I the electron gain enthalpy (i.e., energy released in electron
gain) become less and less negative due to a corresponding increase in the atomic
size.
However, the electron gain enthalpy of F is less negative than that of Cl due to its small
size. Thus, the negative electron gain enthalpy follows the order


`F < Cl > Br > I`
Correct Answer is `=>` (C) `O -> O^(2-)`
Q 1734880752

Electronic configuration of four elements A, B, C, and D are given below

A. `1s^2, 2s^2, 2p^6` B. `1s^2, 2s^2, 2p^4`


C. `1s^2, 2s^2 2p^6 3s^1` D. `1s^2, 2s^2, 2p^5`


Which of the following is the correct order of increasing tendency to gain electron?
NCERT Exemplar
(A)

`A < C < B < D`

(B)

`A < B < C < D`

(C)

`D < B < C < A`

(D)

`D < A < B < C`

Solution:

Electronic confiouration of elements indicate that A is a noble gas (i.e., Ne), 8 is
oxygen (group 16), C is sodium metal (group 1) and D is fluorine (group 17).
(i) Noble gases have no tendency to gain electrons since all their orbitals are
completely filled. Thus, element A has the least electron gain enthalpy.
(ii) Since, element D has one electron less and element 8 has two electrons less than
the corresponding noble gas configuration, hence, element D has the highest
electron, gain enthalpy followed by element B
(iii) Since, element C has one electron in the s-orbital and hence needs one more
electron to complete it therefore, electron gain enthalpy of C is less than that of
element B. Combining all the facts given above, the electron gain enthalpies of the
four elements increase in the order A < C < B < D.
Correct Answer is `=>` (A) `A < C < B < D`
Q 2847156983

Match the properties given in Column I with the metals given in Column II and choose the correct option from the codes given below.

(A)

1 2 3 4

(B)

3 4 2 1

(C)

4 3 2 1

(D)

2 1 4 3

Solution:

Electronic confiouration of elements indicate that A is a noble gas (i.e., Ne), 8 is
oxygen (group 16), C is sodium metal (group 1) and D is fluorine (group 17).
(i) Noble gases have no tendency to gain electrons since all their orbitals are
completely filled. Thus, element A has the least electron gain enthalpy.
(ii) Since, element D has one electron less and element 8 has two electrons less than
the corresponding noble gas configuration, hence, element D has the highest
electron, gain enthalpy followed by element B
(iii) Since, element C has one electron in the s-orbital and hence needs one more
electron to complete it therefore, electron gain enthalpy of C is less than that of
element B. Combining all the facts given above, the electron gain enthalpies of the
four elements increase in the order A < C < B < D.
Correct Answer is `=>` (B) 3 4 2 1
Q 1714880759

Which of the following statements are correct?
NCERT Exemplar

(This question may have multiple correct answers)

(A) Helium has the highest first ionisation enthalpy in the periodic table
(B) Chlorine has less negative electron gain enthalpy than fluorine
(C) Mercury and bromine are liquids at room temperature
(D) In any period, atomic radius of alkali metal is the highest
Solution:

Chlorine has rnore negative electron gain enthalpy than fluorine. Therefore, all other given
statements are correct
Correct Answer is `=>` (A)
Q 1704880758

Which of the following elements will gain one electron more readily in comparison to other elements of their group?
NCERT Exemplar

(This question may have multiple correct answers)

(A) S(g)
(B) Na(g)
(C) O(g)
(D) Cl(g)
Solution:

Chlorine has the highest tendency to gain one electron because by doing so, it acquires the
stable electronic configuration of the nearest noble gas, i.e., argon. Sulphur and oxygen
belong to group 16 but the size of oxygen is much smaller than that of sulphur.


As a result, when an electron is added to them, the electron-electron repulsions in the
smaller 2p- subshell of oxygen are comparatively stronger than those present in the bigger
3p-subshell of sulphur Therefore, S has a h1gher tendency to gain an electron than 0.
Na, on the other hand, 11as only one electron in the valence shell and hence has a strong
tendency to lose rather than gain one electron.
Correct Answer is `=>` (A)
Q 2857756684

The electron affinity of `Be` is similar ar to that of

(A)

`Li`

(B)

`B`

(C)

`Na`

(D)

`Ne`

Solution:

Chlorine has the highest tendency to gain one electron because by doing so, it acquires the
stable electronic configuration of the nearest noble gas, i.e., argon. Sulphur and oxygen
belong to group 16 but the size of oxygen is much smaller than that of sulphur.


As a result, when an electron is added to them, the electron-electron repulsions in the
smaller 2p- subshell of oxygen are comparatively stronger than those present in the bigger
3p-subshell of sulphur Therefore, S has a h1gher tendency to gain an electron than 0.
Na, on the other hand, 11as only one electron in the valence shell and hence has a strong
tendency to lose rather than gain one electron.
Correct Answer is `=>` (D) `Ne`
Q 2867756685

The solubility of hydroxides of group II A increases from `Mg(OH)_2` to `Ba(OH)_2` due to

(A)

increase in lattice energy

(B)

decrease in lattice energy

(C)

increase in ionisation energy

(D)

increase in thermal stability

Solution:

Chlorine has the highest tendency to gain one electron because by doing so, it acquires the
stable electronic configuration of the nearest noble gas, i.e., argon. Sulphur and oxygen
belong to group 16 but the size of oxygen is much smaller than that of sulphur.


As a result, when an electron is added to them, the electron-electron repulsions in the
smaller 2p- subshell of oxygen are comparatively stronger than those present in the bigger
3p-subshell of sulphur Therefore, S has a h1gher tendency to gain an electron than 0.
Na, on the other hand, 11as only one electron in the valence shell and hence has a strong
tendency to lose rather than gain one electron.
Correct Answer is `=>` (B) decrease in lattice energy
Q 1704680558

Which of the following is the correct order of size of the given species
NCERT Exemplar
(A)

`I > I^(-) > I^(+)`

(B)

`I^(+) > I^(-) > I`

(C)

`I > I^(+) > I^(-)`

(D)

`I^(-) > I > I^(+)`

Solution:

Anion formed after the gain of electron to the neutral atom and cation formed after the
lose of electron from outer shell. Hence, cation has smaller size but anion has bigger
size than its neutral atom. Thus, `I^(-) > I > I^(+)`.
Correct Answer is `=>` (D) `I^(-) > I > I^(+)`
Q 2877756686

Fluorine, the most electronegative element in Paulings scale have the value

(A)

`1`

(B)

`2`

(C)

`3`

(D)

`4`

Solution:

Anion formed after the gain of electron to the neutral atom and cation formed after the
lose of electron from outer shell. Hence, cation has smaller size but anion has bigger
size than its neutral atom. Thus, `I^(-) > I > I^(+)`.
Correct Answer is `=>` (D) `4`
Q 1724180951

In which of the following options order of arrangement does not agree with the variation of property indicated against it?

NCERT Exemplar

(This question may have multiple correct answers)

(A) `Al^(3+) < Mg^(2+) < Na^+ < F^(-) text(lncreasing ionic size)`
(B) `B < C < N < O text( Increasing first ionisation enthalpy)`
(C) `I < Br < Cl < F text(Increasing electron gain enthalpy)`
(D) `Li < Na < K < Rb text( Increasing metallic radius)`
Solution:

Due to greater stability of the half filled electronic configuration of n'1trogen, its ionisation
enthalpy is higher than that of oxygen. Thus, option (b) is incorrect.
Due to stronger electron-electron repulsions in the small size of flourine the negative electron
gain enthalpy of fluorine is lower tllan t11at of chlorine. Hence, option (c) is incorrect.
Correct Answer is `=>` (B)
Q 2817056880

The first ionisation potential of `Na, Mg , Al , Si` are in the order

(A)

`Na > Mg > Al > Si`

(B)

`Na < Mg < Al < Si`

(C)

`Na < Si < Al < Mg`

(D)

`Na < Al < Mg < Si`

Solution:

Due to greater stability of the half filled electronic configuration of n'1trogen, its ionisation
enthalpy is higher than that of oxygen. Thus, option (b) is incorrect.
Due to stronger electron-electron repulsions in the small size of flourine the negative electron
gain enthalpy of fluorine is lower tllan t11at of chlorine. Hence, option (c) is incorrect.
Correct Answer is `=>` (D) `Na < Al < Mg < Si`
Q 1774580456

The first ionisation enthalpies of Na, Mg, Al and Si are in the order
NCERT Exemplar
(A)

`Na < Mg < Al < Si`

(B)

`Na > Mg > Al > Si`

(C)

`Na < Mg < Al < Si`

(D)

`Na > Mg > Al < Si`

Solution:

Follow the following steps to solve out such problems
Correct Answer is `=>` (A) `Na < Mg < Al < Si`
Q 2857056884

Ionic radii of zirconium and hafnium beconw almost identical because

(A)

They are d - block elements

(B)

they belong to the same group

(C)

of increased nuclear charge

(D)

of anthande contraction

Solution:

Follow the following steps to solve out such problems
Correct Answer is `=>` (D) of anthande contraction
Q 2877056886

Which of the following statements concerning ionisation energy is not correct?

(A)

the second ionisation energy is always more than the first

(B)

With in a group, there is a gradual increaces in ionisation energy because nuclear charge increases

(C)

Ionisation energy of the Be is more then B

(D)

Ionisation energy of noble gases are high

Solution:

Follow the following steps to solve out such problems
Correct Answer is `=>` (B) With in a group, there is a gradual increaces in ionisation energy because nuclear charge increases
Q 2837156982

Match List I with List II and select the correct combination of ions and isoelectronic ions using the codes given below the lists.

(A)

3 1 2 4

(B)

3 1 4 2

(C)

4 2 1 3

(D)

4 2 3 1

Solution:

Follow the following steps to solve out such problems
Correct Answer is `=>` (B) 3 1 4 2

Properties of Group `IA` and `IIA`

Q 1764880755

Those elements impart colour to the flame on heating in it, the atoms of which require Low energy for the ionisation (i.e., absorb energy in the visible region of spectrum). The elements of which of the following groups will impart colour to the flame ?
NCERT Exemplar

(This question may have multiple correct answers)

(A) 2
(B) 13
(C) 1
(D) 1 7
Solution:

The elements of group 1 (alkali metals) and group 2 (alkaline earth metals) have 1 and 2
electrons respectively in their valence shells and hence have low ionisation energies. In
other words, elements of group 1 and 2 imparts colour to the flame.
Correct Answer is `=>` (A)
Q 2807156088

Which of the following has least density ?

(A)

`Na`

(B)

`Li`

(C)

`Mg`

(D)

`k`

Solution:

The elements of group 1 (alkali metals) and group 2 (alkaline earth metals) have 1 and 2
electrons respectively in their valence shells and hence have low ionisation energies. In
other words, elements of group 1 and 2 imparts colour to the flame.
Correct Answer is `=>` (B) `Li`
Q 2847356283

All alkaline earth metal ions are

(A)

coloured

(B)

colourless

(C)

paramagnetic

(D)

colourless and diamagnetic

Solution:

The elements of group 1 (alkali metals) and group 2 (alkaline earth metals) have 1 and 2
electrons respectively in their valence shells and hence have low ionisation energies. In
other words, elements of group 1 and 2 imparts colour to the flame.
Correct Answer is `=>` (D) colourless and diamagnetic

Properties of Group `IIIA`, `IVA`, `VA`, `VIA`, `VIIA` and Zero Group

Q 2837145982

Group number and valency has no relation in

(A)

zero group

(B)

first group

(C)

IIIrd group

(D)

VII group

Solution:

The elements of group 1 (alkali metals) and group 2 (alkaline earth metals) have 1 and 2
electrons respectively in their valence shells and hence have low ionisation energies. In
other words, elements of group 1 and 2 imparts colour to the flame.
Correct Answer is `=>` (A) zero group
Q 2837156082

Zero group was introduced by

(A)

Lather Meyer

(B)

Mendeleev

(C)

Ramsay

(D)

Lockyer

Solution:

The elements of group 1 (alkali metals) and group 2 (alkaline earth metals) have 1 and 2
electrons respectively in their valence shells and hence have low ionisation energies. In
other words, elements of group 1 and 2 imparts colour to the flame.
Correct Answer is `=>` (C) Ramsay
Q 2857456384

The common semiconductor material is

(A)

nitrogen

(B)

phosphorus

(C)

antimony

(D)

arsenic

Solution:

The elements of group 1 (alkali metals) and group 2 (alkaline earth metals) have 1 and 2
electrons respectively in their valence shells and hence have low ionisation energies. In
other words, elements of group 1 and 2 imparts colour to the flame.
Correct Answer is `=>` (C) antimony
Q 2887056887

All the elements in a group (family) have a common valency, e.g. all the elements or the carbon family (carbon, silicon , germanium tin and lead) have common valency four. However. some of the these elements can also have
valency two which of the following have valency two?

(A)

Silicon, garmanium and tin

(B)

garmanium and tin

(C)

garmanium tin and lead

(D)

tin and lead

Solution:

The elements of group 1 (alkali metals) and group 2 (alkaline earth metals) have 1 and 2
electrons respectively in their valence shells and hence have low ionisation energies. In
other words, elements of group 1 and 2 imparts colour to the flame.
Correct Answer is `=>` (C) garmanium tin and lead
Q 2867856785

`Al` and `Ga` have the same covalent radius because of

(A)

greater shielding power of s - electrons of Ga-atom

(B)

poor shielding power of s-electrons of Ga-atom

(C)

poor shielding power of d-electrons of Ga-atom

(D)

greater shielding power of d - electrons of Ga-atom

Solution:

The elements of group 1 (alkali metals) and group 2 (alkaline earth metals) have 1 and 2
electrons respectively in their valence shells and hence have low ionisation energies. In
other words, elements of group 1 and 2 imparts colour to the flame.
Correct Answer is `=>` (C) poor shielding power of d-electrons of Ga-atom
Q 2837056882

Anomalous behaviour of nitrogen is due to

(A)

small size and high electronegativity

(B)

non - availability of d-orbital in valence

(C)

ease of multiple bond formation

(D)

All of the above are correct

Solution:

The elements of group 1 (alkali metals) and group 2 (alkaline earth metals) have 1 and 2
electrons respectively in their valence shells and hence have low ionisation energies. In
other words, elements of group 1 and 2 imparts colour to the flame.
Correct Answer is `=>` (D) All of the above are correct
Q 2817056889

The best and the poorest conductors of heat are respectively

(A)

silver (`Ag`) and lead (`Pb`)

(B)

copper `(Cu)` and aluminium `(Al)`

(C)

silver `(AQ)` ancl gold `(Au)`

(D)

copper `(Cu)` and gold `(Au)`

Solution:

The elements of group 1 (alkali metals) and group 2 (alkaline earth metals) have 1 and 2
electrons respectively in their valence shells and hence have low ionisation energies. In
other words, elements of group 1 and 2 imparts colour to the flame.
Correct Answer is `=>` (A) silver (`Ag`) and lead (`Pb`)

Properties of Transition Elements

Q 2827856781

Identify the incorrect statement among the following.

(A)

ci·block elements show irregular and erratic chemical properties among themselves

(B)

La and Lu llave partially filled d-orbilals and no other partially filled orbitals

(C)

The chemistry of various lanthanoids is very similar

(D)

4f and 5f-orbitals are equally shielded

Solution:

The elements of group 1 (alkali metals) and group 2 (alkaline earth metals) have 1 and 2
electrons respectively in their valence shells and hence have low ionisation energies. In
other words, elements of group 1 and 2 imparts colour to the flame.
Correct Answer is `=>` (D) 4f and 5f-orbitals are equally shielded
Q 2877156986

Which one of the following is a transition metal ?

(A)

Aluminium

(B)

Manganese

(C)

Magnesium

(D)

Calcium

Solution:

The elements of group 1 (alkali metals) and group 2 (alkaline earth metals) have 1 and 2
electrons respectively in their valence shells and hence have low ionisation energies. In
other words, elements of group 1 and 2 imparts colour to the flame.
Correct Answer is `=>` (B) Manganese
Q 2817167080

Which one of tho following elements exists in liquid state at room temperature?

(A)

mercury

(B)

Lead

(C)

Sodium

(D)

Calcium

Solution:

The elements of group 1 (alkali metals) and group 2 (alkaline earth metals) have 1 and 2
electrons respectively in their valence shells and hence have low ionisation energies. In
other words, elements of group 1 and 2 imparts colour to the flame.
Correct Answer is `=>` (A) mercury
Q 2857556484

Which of the following is most abundant transition element ?

(A)

Copper

(B)

Iron

(C)

Zinc

(D)

Nickel

Solution:

The elements of group 1 (alkali metals) and group 2 (alkaline earth metals) have 1 and 2
electrons respectively in their valence shells and hence have low ionisation energies. In
other words, elements of group 1 and 2 imparts colour to the flame.
Correct Answer is `=>` (B) Iron
 
SiteLock