$$\mathrm { MgO } < \mathrm { NiO } < \mathrm { K } _ { 2 } \mathrm { O } < \mathrm { CS } _ { 2 } {O } $$ (basic strength )

$$\mathrm { Cs } ^ { + } solution)

$$\mathrm { Li } _ { 2 } \mathrm { CO } _ { 3 } < \mathrm { Na } _ { 2 } \mathrm { CO } _ { 3 } < \mathrm { K } _ { 2 } \mathrm { CO } _ { 3 }$$ (solubility order)

$$\mathrm { NH } _ { 3 } < \mathrm { PH } _ { 3 } < \mathrm { AsH } _ { 3 }$$ (thermal stability)

MCQ Questions for Class 11 Medical Chemistry The S-Block Elements Quiz 1

Which of the following is organometalic compound

0%
Methyl lithium
0%
Lithium methoxide
0%
Lithium dimethyl amide
0%
Lithium acetate

Explanation

$LiCH_3$ have metal carbon bond so considered organometic compound and other do not have.

Incorrect statement about given carbohydrate is

0%
Above compound is a reducing sugar
0%
Above compound undergo mutarotation
0%
Above compound is a non-reducing sugar
0%
Above compound has a glycosidic linkage

Which of the following product is obtained when bleaching powder is distilled with acetone?

0%
$CCl_4$
0%
$CH_2Cl_2$
0%
$CH_3 -CH_3$
0%
none of the above

Lithium react less vigorously with water than other metals. Give reason behind it.

0%
Lithium has most negative $E^\ominus$ value
0%
Lithium has small size and very high hydration energy.
0%
Lithium has least negative $E^\ominus$ value
0%
Both (a) and (b)

Diagonal relationship is found in between

0%
$Be-Al$
0%
$B-C$
0%
$Li-Mg$
0%
$A\ and\ C\ both$

The alkaline earth metal ion present in chlorophyll is

0%
$Ca$
0%
$Mg$
0%
$Be$
0%
$Ba$

Among the alkaline earth metals, the element forming predominantly covalent compounds is

0%
Be
0%
Ba
0%
Ca
0%
Mg

The ionization energy of a hydrogen atom is 13.6eV. The energy of the third-lowest electronic level in doubly ionized lithium (Z=3) is:

0%
-28.7eV
0%
-54.4eV
0%
-122.4eV
0%
-13.6eV

Correct order is :

0%
$\mathrm { MgO } < \mathrm { NiO } < \mathrm { K } _ { 2 } \mathrm { O } < \mathrm { CS } _ { 2 } {O }$ (basic strength )
0%
$\mathrm { Cs } ^ { + } < \mathrm { K } ^ { + } < \mathrm { Mg } ^ { 2 + } < \mathrm { Be } ^ { 2 + }$ (ionic moblity in aqueous
solution)
0%
$\mathrm { Li } _ { 2 } \mathrm { CO } _ { 3 } < \mathrm { Na } _ { 2 } \mathrm { CO } _ { 3 } < \mathrm { K } _ { 2 } \mathrm { CO } _ { 3 }$ (solubility order)
0%
$\mathrm { NH } _ { 3 } < \mathrm { PH } _ { 3 } < \mathrm { AsH } _ { 3 }$ (thermal stability)

The melting point of lithium (181

$^\circ$ C) is just double the melting point of sodium (98

$^\circ$ C) because

0%
down the group, the hydration energy decreases
0%
down the group, the ionization energy decreases
0%
down the group, the cohesive energy decreases
0%
None of these

Which of the following are arranged in increasing order of solubilities?

0%
$CaCO_3 < KHCO_3 < NaHCO_3$
0%
$NaHCO_3 < KHCO_3 < CaCO_3$
0%
$KHCO_3 < NaHCO_3 < CaCO_3$
0%
$CaCO_3 < NaHCO_3 < KHCO_3$

Incorrect statement is:

0%
$NaHCO_{3}$ and $KHCO_{3}$ have same crystal structure
0%
On heating $LiNO_{3}$ decomposes into $LiO_{2}$ and $NO_{2}$
0%
Among alkali metals, $Li$ metal impart red colour to flame
0%
$Li_{2}SO_{4}$ does not from alum

Which of the following carbonate is not stable to heat.

0%
$Li_2CO_3$
0%
$Na_2CO_3$
0%
$K_2CO_3$
0%
$Rb_2CO_3$

Which element is most alkaline :

0%
F
0%
CI
0%
Br
0%
I

Which of the following statements is false ?

0%
${\text{M}}{{\text{g}}^{{\text{2 + }}}}$ ion form a complex with ATP
0%
${\text{C}}{{\text{a}}^{{\text{2 + }}}}$ on are important in blood clotting
0%
${\text{C}}{{\text{a}}^{{\text{2 + }}}}$ ion are not important in maintaining the regular beating of the heart.
0%
${\text{M}}{{\text{g}}^{{\text{2 + }}}}$ ion are important in the green parts of plants.

Which of the following is a binary compound?

0%
${ K }_{ 2 }C{ O }_{ 3 }$
0%
$HCl{ O }_{ 4 }$
0%
${ H }_{ 2 }O$
0%
${ H }_{ 2 }S{ O }_{ 4 }$

Which of the following statement is false?

0%
$Mg^{2+}$ ion forms a complex with $ATP$
0%
$Ca^{2+}$ ions are important in blood clotting.
0%
$Ca^{2+}$ ions are not important in maintaining the regular beating of the hear
0%
$Mg^{2+}$ ions are important in the green parts of plants

Passivity is exhibited by:

$A) Be , B) Mg, C) Al ,D) B$

0%
$A, B$
0%
$B, C$
0%
$A, C$
0%
$B, D$

Which of the following enzymes contain

$Mg^{2+}$
ions?

0%
Phosphohydrylase
0%
Zymase
0%
Phosphotransferase
0%
1 and 3

Explanation

$Mg^{2+}$ ions are present in enzymes phosphohydrylase and phosphotransferase.

The polarising power of

$Be^{2+}$ is nearly same as that of:

0%
$Ba^{2+}$
0%
$Mg^{2+}$
0%
$Al^{3+}$
0%
$B^{3+}$

Explanation

Both

$Be^{2+}$ and

$Al^{3+}$ show diagonal relationship with each other. They have nearly same polarizing power.

Bones and teeth contain:

0%
Calcium dihydrogen phosphate
0%
Apatite
0%
Calcium phosphide
0%
None of the above

Explanation

Bones and teeth contains Apatite which is a group of phosphate minerals and contains calcium. Its formula can be represented as

$Ca_5(PO_4)_3(F,Cl,OH)$ .

Aluminium forms aluminates like beryllium forms:

0%
fluorides
0%
nitrates
0%
beryllates
0%
silicates

Explanation

Beryllium forms beryllates such as sodium beryllate

$(Na_2BeO_2)$ . Similarly aluminum form aluminates such as sodium aluminate

$(NaAlO_2)$ .

The polarising power of

$Mg^{2+}$ is nearly same as that of:

0%
$Li^{+}$
0%
$Ba^{2+}$
0%
$Al^{3+}$
0%
all of the above

Explanation

$Li^+$ and

$Mg^{2+}$ show diagonal relationship. They have nearly similar polarizing power.

Alkaline earth metals have only positive oxidation state. This is due to their:

0%
high melting points
0%
high electronegativity
0%
softness
0%
low ionization potential

The main oxides formed on combustion of

$Li, Na$ and

$K$ in excess of air are, respectively:

0%
$Li{O}_{2}, {Na}_{2}{O}_{2}$ and ${K}_{2}O$
0%
${Li}_{2}{O}_{2}, {Na}_{2}{O}_{2}$ and $K{O}_{2}$
0%
${Li}_{2}O, {Na}_{2}{O}_{2}$ and $K{O}_{2}$
0%
${Li}_{2}O, {Na}_{2}O$ and $K{O}_{2}$

Explanation

The main oxides formed on combustion of

$Li\ ,Na$ and

$K$ in excess of air are, respectively

$\displaystyle {Li}_{2}O, {Na}_{2}{O}_{2}$ and

$\displaystyle K{O}_{2}$ .

Under ordinary conditions, lithium forms the monoxide, sodium forms the peroxide and other alkali metals form superoxide.

Hence, the correct option is $C$ .

The element having greatest difference between its first and second ionization energies is:

0%
$Ca$
0%
$K$
0%
$Ba$
0%
$Se$

Explanation

$K=2,8,8,1$

After removal of one electron, the second electron we have to remove from another shell which has an octet configuration, hence there is a large difference between first and second ionization energies.

The correct sequence of thermal stability of the following carbonates is:

0%
$BaCO_3 < CaCO_3 < SrCO_3 < MgCO_3$
0%
$MgCO_3 < CaCO_3 < SrCO_3 < BaCO_3$
0%
$BaCO_3 < SrCO_3 < CaCO_3 < MgCO_3$
0%
$MgCO_3 < SrCO_3 < CaCO_3 < BaCO_3$

Explanation

The thermal stability of alkaline earth metals carbonates increases down the group because down the group polarizing power of cation decreases. So thermal stability increases.

Hence, thermal stability order :

$MgCO_3<CaCO_3<SrCO_3<BaCO_3$

Both lithium and magnesium display several similar properties due to the diagonal relationships however, the one which is incorrect is:

0%
Both form soluble bicarbonates.
0%
Both form nitrides.
0%
Nitrates of both $Li$ and $Mg$ yield $NO_2$ and $O_2$ on heating.
0%
Both form basic carbonates.

Explanation

Both

$Li$ and

$Mg$ combine directly with

$N_2$ to give nitrides

$Li_3N_2$ and

$Mg_3N_2$ .

Bicarbonates of

$Li$ and

$Mg$ are more soluble in water than carbonates whereas carbonates of alkali metals are more soluble.

Hydroxides and nitrates of both Li and Mg decompose on heating to give oxide.

$LiNO_3 \xrightarrow {\Delta} Li_2O +NO_2+O_2$

$Mg(NO_3)_2 \xrightarrow {\Delta} MgO+NO_2+O_2$

Magnesium forms basic carbonates

$(MgCO_3.Mg(OH)_2.xH_2O)$ while lithium forms normal carbonates, it does not form basic carbonates.

The structure of beryllium chloride in the solid state and vapour phase, respectively, are:

0%
chain and dimeric
0%
chain and chain
0%
dimeric and dimeric
0%
dimeric and chain

Explanation

$BeCl_{2}$ exist as

$(BeCl_{2})_{n}$ polymeric chain in solid form, while

$BeCl_{2}$ exist as dimer

$(BeCl_{2})_{2}$ in vapour phase.

The oxide of an element whose electronic configuration

$1s^22s^22p^63s^1$ is:

0%
Neutral
0%
Atmospharic
0%
Basic
0%
Acidic

The INCORRECT statement is :

0%
Lithium is least reactive with water among the alkali metals.
0%
$LiCl$ crystallises from aqueous solution as $LiCl.2H_2O$ .
0%
Lithium is the strongest reducing agent among the alkali metals.
0%
$LiNO_3$ decomposes on heating to give $LiNO_2$ and $O_2$

Explanation

$2LiNO_3 \xrightarrow{\Delta} Li_2O + 2NO_2{(g)} +\dfrac{1}{2}O_2(g)$

So, D is the correct option.

The amphoteric hydroxide is :

0%
$Ca(OH)_2$
0%
$Be(OH)_2$
0%
$Sr(OH)_2$
0%
$Mg(OH)_2$

Explanation

$Be(OH)_2$ is amphoteric in nature while rest all alkaline earth metal hydroxide are basic in nature

Among the statements

$(a)-(d)$ , the correct ones are :

(a) Lithium has the highest hydration enthalpy among the alkali metals.

(b) Lithium chloride is insoluble in pyridine.

(d) Both lithium and magnesium react slowly with

$H_2O$ .

0%
(b) and (c) only
0%
(a), (b) and (d) only
0%
(a), (c) and (d) only
0%
(a) and (d) only

All of the following share the same crystal structure except:

0%
$RbCl$
0%
$NaCl$
0%
$LiCl$
0%
$KCl$

Explanation

RbCl, NaCl, and KCl share the same crystal structure except for LiCl.

LiCl is deliquescent. It crystalises as a hydrate

$\displaystyle LiCl \cdot 2H_2O$ . Other alkali metal chlorides do not form hydrates.

Hence ,option C is correct.

Ionic mobility of which of the following alkali metal ions is the lowest when aqueous solution of their salts are put under an electric field?

0%
$Li$
0%
$Na$
0%
$K$
0%
$Rb$

Explanation

All the alkali metal ion exists as hydrated ions $M^+ (H_2O)_n$ in it's an aqueous solution.

The degree of hydration decreases as the ionic size increases when we go down the group. Since the mobility of ions is inversely proportional to the size of their hydrated ions, the increasing order of ionic mobility is

$Li^+ < Na^+ < K^+ < Rb^+$

What is the value of electron gain enthalpy of

${Na}^{+}$ if

$I{E}_{1}$ of

$NA = 5.1 eV$ ?

0%
$-5.1 eV$
0%
$-10.2 eV$
0%
$+2.55 eV$
0%
$+10.2 eV$

Explanation

The electron gain enthalpy of sodium cation is equal in magnitude and opposite in sign to the first ionization energy of sodium atom. It is equal to

$-5.1 eV$ .

Beryllium and aluminum exhibit many properties which are similar. But the two elements differ in:

0%
maximum covalency in compounds
0%
exhibiting amphoteric nature in their oxides
0%
forming covalent halides
0%
forming polymeric hydrides

Explanation

$Be$ exhibits maximum covalency of four whereas

$Al$ shows maximum covalency of six.

0%
Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
0%
Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
0%
Assertion is correct but Reason is incorrect
0%
Both Assertion and Reason are incorrect

Explanation

The carbonate of lithium decomposes easily on heating to form lithium oxide and

$CO_2$ . Other alkali metal carbonates do not decompose.

$Li_2CO_3 \xrightarrow{\Delta } Li_2O + CO_2 \uparrow$

Lithium being very small in size polarises large carbonate ion. It distorts the electron cloud on the nearby oxygen atom of large carbonate ion. It weakens

$C-O$ bond and strengthens

$Li-O$ bond. It leads to the formation of more stable

$Li_2O$ and

$CO_2$ .

Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.

Formation of polyethylene from calcium carbide takes place is follows :

$CaC_2 + 2H_2O \rightarrow Ca(OH)_2 + C_2H_2$

$C_2H_2 +H_2 \rightarrow C_2H_4$

$nC_2H_4 \rightarrow +CH_2 - CH_2 +n$

The amount of polyethylene obtained from 64.0 kg of

$CaC_2$ is:

0%
27 kg
0%
24 kg
0%
22 kg
0%
28 kg

Explanation

Mass of

$Ca{ C }_{ 2 }$ =

$64$ Kg

Moles of

$Ca{ C }_{ 2 }$ = 64/64 =

$1000$ mol

$CaC_2 + 2H_2O \rightarrow Ca(OH)_2+C_2H_2$

For 1000 mole of

$Ca{ C }_{ 2 }$ , We get 1000 mole of

${ C }_{ 2 }{ H }_{ 2 }$

$C_2H_2+H_2\rightarrow C_2H_4$

For 100 mole of

${ C }_{ 2 }{ H }_{ 2 }$ , we get 1000 mole of

${ C }_{ 2 }{ H }_{ 4 }$

$nC_2H_4\rightarrow (CH_2-CH_2)_n$

For n mole

${ C }_{ 2 }{ H }_{ 2 }$ , we get 1 mole of polyethene.

For 1000 mole of

${ C }_{ 2 }{ H }_{ 2 }$ , we get

$(\dfrac { 1000 }{ n } )\times 1$

Number of moles of polyethylene formed are 1000/n.

Molecular weight of polyethylene is

$n\times [(2\times 12)+(2\times 4)]=28n$

Mass of polyethylene produced

$=$ Number of moles

$\times$ Molecular weight

$=(\dfrac { 1000 }{ n } )\times 28n$

$=28000$ gram

$=28$ kg

Option D is correct.

The correct order of solubility of the following compound in water is:

0%
$Ba(OH)_2 < Mg(OH)_2$
0%
$BaCO_3 > CaCO_3$
0%
$Ca(OH)_2=Mg(OH)_2$
0%
$CaSO_4 < MgSO_4$

Explanation

With increase in the size of the central metal ion, the solubility of the sulphates of alkaline earth metals decreases as the hydration enthalpy from

$Be^{2+}$ to

$Ba^{2+}$ decreases down the group.

Therefore ,

$MgSO_4$ is more soluble in water than

$CaSO_4$ .

Read the assertion and reason carefully and answer the question on the basis of the following options. You have to select the one that best describes the two statements.

Assertion: Potassium and caesium are used in photoelectric cells.
Reason: Potassium and caesium emit electrons on exposure to light.

0%
If both assertion and reason are true and the reason is a correct explanation of the assertion
0%
If both assertion and reason are true but reason is not a correct explanation of the assertion
0%
If the assertion is true but reason is false
0%
If both the assertion and reason are false
0%
If the assertion is false but the reason is true

Which of the following has the highest tendency to give the following reaction?

${ M }_{ (g) }^{ + }\xrightarrow [ medium ]{ aqueous } { M }_{ (aq) }^{ + }$

0%
$Na$
0%
$Li$
0%
$K$
0%
$Rb$

Explanation

Because of its smallest size,

$Li^+$ ions highest hydration energy and hence highest stability of hydrated

$Li^+$ ion.

Sodium hydroxide reacts with

$SO_2$ in aqueous medium to give:

0%
$\displaystyle { NaHSO }_{ 3 }$
0%
$\displaystyle { Na }_{ 2 }{ S }_{ 2 }{ O }_{ 3 }$
0%
$\displaystyle NaH{ SO }_{ 4 }$
0%
$\displaystyle { Na }_{ 2 }{ SO }_{ 3 }$

Explanation

Sodium hydroxide on reaction with sulphur dioxide forms sodium sulphite and water. The reaction is:

$2NaOH + SO_2\rightarrow Na_2SO_3 +H_2O$ .

Hence option D is correct.

What is the main reason of diagonal relationship between lithium and magnesium?

0%
Electronegativity remains constant the same on moving parallel.
0%
Electronegativity remains constant the same on moving horizontally.
0%
Electronegativity remains constant the same on moving diagonally.
0%
Electronegativity remains constant the same on moving vertically.

The most active metal is:

0%
$Be$
0%
$Ca$
0%
$Ba$
0%
$Mg$

Explanation

On moving down the group, the electropositive character increases. Hence, the chemical reactivity also increases from Be to Ba.

Therefore, the most active metal in alkaline earth metal is barium

$(Ba)$ .

Hence, option

$(C)$ is correct.

A nuclide of an alkaline earth metal undergoes radioactive decay by emission of the

$\alpha$ -particles is succession. The group of the periodic table to which the resulting daughter element would belong is :-

0%
Gr. 4
0%
Gr.6
0%
Gr.16
0%
Gr.14

Among the alkali metals, the metal with the highest ionisation potential is:

0%
Na
0%
Li
0%
Rb
0%
Cs

Radium is a harmful element which emits radiation.

0%
True
0%
False

Diagonal relationship of elements in due to same:

0%
size
0%
mass number
0%
atomic number
0%
electron affinity

The correct sequence of increasing melting point of

$BeCl_{2},MgCl_{2},CaCl_{2},SrCl_{2}$ and

$BaCl_{2}$ is

0%
$BaCl_{2} < SrCl_{2} < CaCl_{2} < MgCl_{2} < BeCl_{2}$
0%
$BeCl_{2} < MgCl_{2} < CaCl_{2} < SrCl_{2} < BaCl_{2}$
0%
$BeCl_{2} < CaCl_{2} < MgCl_{2} < SrCl_{2} < BaCl_{2}$
0%
$MgCl_{2} < BeCl_{2} < SrCl_{2} < CaCl_{2} < BaCl_{2}$

Explanation

Ionic character depends upon, electronegativity difference between cation and anion of the compound. As these difference increases, the ionic character increases. The larger the size of cation and the smaller the size of anion, the more is the electronegativity difference and the more is the ionic character. as here anion is same and sequence of the size of the cation is

$Be^{2+}<Mg^{2+}<Ca^{2+}<Sr^{2+}<Ba^{2+}$

So the correct order of M.P is as follows:

$BeCl_2<MgCl_2<CaCl_2<SrCl_2<BaCl_2$ Hence, option B is correct

CBSE Questions for Class 11 Medical Chemistry The S-Block Elements Quiz 1 - MCQExams.com

0:0:1

Practice Class 11 Medical Chemistry Quiz Questions and Answers

CBSE Questions for Class 11 Medical Chemistry The S-Block Elements Quiz 1 - MCQExams.com

0:0:1

Practice Class 11 Medical Chemistry Quiz Questions and Answers

Support mcqexams.com by disabling your adblocker.