Explore topic-wise InterviewSolutions in Current Affairs.

This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.

1.

Magneson reagent is used to detect

Answer»

 `Mn^2+`
`Mg^(2+)`
`PO_(4)^(3-)`
 `MnO_(4)^(-)`

ANSWER :B
2.

Magnesium (Z=12) has isotopes that range form Mg-20, "to"Mg-31, "Only" Mg-24, Mg-25,andMg-26 are not radioactive. What mode of radioactive deacy would convert. What mode of radioavtive deacy would convert Mg-20, Mg-21, Mg-22, and Mg-23 into stable isotopes most quickly?

Answer»

ELECTRON emission
Alpha PARTICLE emission
Gamma emissin
Positron emission

Answer :D
3.

Magnesium wire burns in the atmosphere of CO_2 because:

Answer»

Magnesium acts as an OXIDISING agent
Magnesium has TWO electrons in the outermost orbit
Magnesium acts as a reducing agent and removes oxygen from `CO_2`
NONE of these

Answer :C
4.

Magnesium reduces SO_(2) and gives :

Answer»

`SO_(3)`
`H_(2)SO_(4)`
MG `S_(2)O_(3)`
S

Answer :D
5.

Magnesium reacts with an element (X) to form an ionic compound. If the ground state electronic configuration of (X) is 1s^(2)2s^(2)2p^(3), the simplest formula for this compounds is

Answer»

`Mg_2X_(3)`
`MgX_(2)`
`Mg_(2)X`
`Mg_(3)X_(2)`

Solution :Magnesium ion =`MG^(+2)`
6.

Magnesium reacts with acids producing hydrogen and corresponding magnesium salts. In such reactions magnesium undergoes :

Answer»

OXIDATION
Reduction
Nither oxidation nor reduction
Simple dessoution

Answer :A
7.

Magnesium present in the sea water is precipitated using 'X' and precipitated as 'Y'. M Here 'X' abd 'Y' are respectively

Answer»

`CaCO_3 andMgCO_3`
`CaCO_3 andMg(OH)_2`
`CA(OH)_2andMg (OH)_2`
`Ca(OH_2)and MgCO_3`

ANSWER :C
8.

Magnesium oxide is reduced in the Hansging method using

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Silicon
Ferro-silicon
Coke
Calcium carbide

Answer :C
9.

Magnesium oxide has the NaCl structure and radii of Mg^(2+) and O^(2–) ions are 0.86 A and 1.24 A. Determine the density of magnesium oxide solid.

Answer»

Solution : In a unit cell, there are four unit of MgO and edge- LENGTH of the unit cell is
a = 2 (RADIUS of cation+radius of anion)
= 2 (0.86 + 1.24) = 4.2 Å
Density `(rho)=(4x40)/(6.023xx10^(23)(4.2xx10^(10^(-8)))^(3))=3.585 g//cc`
10.

Magnesium on heating reacts vigorously with element X to produce compound Y. An aqueous solution of Y, when treated with aqueous silver nitrate , gives a white precipitate that is readily soluble in dilute aqueous ammonia. What is the minium mass of X that is needed to react completely with 4.05g of magnesium

Answer»

11.83g
5.92g
5.33g
2.67g

Answer :A
11.

Magnesium metal when burns in air gives a mixture of its nitride & oxide. When dissolved in water the solution becomes basis because of NH_(3) & metal hydroxide. 39.2 gm sample of pure magnesium is reacted with 82.1 litre of air (containing only N_(2) & O_(2) in 4:1 molar ratio) at 1 atm & 300 K to form a mixture of nitride & oxide labelled as micture I such that all magnesium & one of the gases get completely consumed. this mixture is dissolved in water which is labelled as micture II. based on this information, answer the questions that follows. What is the molar ratio in which MgO & Mg_(3)N_(2) will be present respectively in mixture I ?

Answer»

`40/9`
`9/40`
`1:3`
`3:1`

12.

Magnesium metal when burns in air gives a mixture of its nitride & oxide. When dissolved in water the solution becomes basis because of NH_(3) & metal hydroxide. 39.2 gm sample of pure magnesium is reacted with 82.1 litre of air (containing only N_(2) & O_(2) in 4:1 molar ratio) at 1 atm & 300 K to form a mixture of nitride & oxide labelled as micture I such that all magnesium & one of the gases get completely consumed. this mixture is dissolved in water which is labelled as micture II. based on this information, answer the questions that follows. which gas will be left unreacted inair & by how much ?

Answer»

`N_(2(G)), 7.7/3` MOLES
`O_(2), 0.6` moles
`N_(2(g)), 2` moles
`O_(2),1.7/3` moles

ANSWER :A
13.

Magnesium obtained by the electrolysis of fused MgCl_(2) using

Answer»

a nickel cathode and graphite anode
a nickel container as cathode and an IRON anode
an iron container as cathode and graphite anode
a LEAD cathode and a platinum anode

Answer :C
14.

Magnesium metal when burns in air gives a mixture of its nitride & oxide. When dissolved in water the solution becomes basis because of NH_(3) & metal hydroxide. 39.2 gm sample of pure magnesium is reacted with 82.1 litre of air (containing only N_(2) & O_(2) in 4:1 molar ratio) at 1 atm & 300 K to form a mixture of nitride & oxide labelled as micture I such that all magnesium & one of the gases get completely consumed. this mixture is dissolved in water which is labelled as micture II. based on this information, answer the questions that follows. If mixture II is reacted with 0.1M H_(2)SO_(4) for complete neutralisation +volume of H_(2)SO_(4) solution required will be approximately .

Answer»

1733 ML
2333 ml
1633 ml
1833 ml

15.

Magnesium metal is prepared by:

Answer»

Reduction of MgO by coke
Electrolysis of AQUEOUS solution of `MG(NO_3)_2`
Displacement of Mg by iron from MAGNESIUM sulphate solution
Electrolysis of MOLTEN magnesium chloride

Answer :D
16.

Magnesium metal is extracted from

Answer»

Camallite
MAGNESITE
SEA wate
All of these

ANSWER :D
17.

Magnesium is manufactured by electrolysing fused magnesium chloride using :

Answer»

a nickel cathode and a GRAPHITE ANODE
the IRON container as anode and a nickel cathode
the iron container as cathode and a graphite anode
the nickel container as cathode and iron anode

Answer :C
18.

Magnesium is present in

Answer»

haemoglobin
chlorophyll
casein
keratin

Answer :B
19.

Magnesium is present in :

Answer»

Haemoglobin
Chlorophyll
Vitamin `B_(12)`
ASCORBIC acid

Answer :B
20.

Magnesium is not precipitated from a solution of its salt by a mixture of NH_4 OH and NH_4 CI.Explain.

Answer»

Solution :Magnesium has to precipitate as `Mg(OH)_2` when treated with `NH_4OH`, but ADDITION of `NH_4CI` will SUPPRESS the ionisation of `NH_4OH` due to common ion EFFECT. So ionic product of `Mg^(2+) and OH^(-)` ions will be less than the solubility product `(K_(sp))` of`Mg(OH)_2`. HENCE will not precipitate.
21.

Magnesium is not present in :

Answer»

CRYOLITE
DOLOMITE
Carnollite
EPSOM salt.

Answer :A
22.

Magnesium is extracted by electrolysis of fused magnesium chloride using :

Answer»

NICKEL container as cathode and iron anode
Iron container as anode and nickel cathode.
Iron container as cathode and graphite anode.
Nickel container as cathode and graphite anode.

Solution :`((w)/(40))_(NaOH)=((w)/(36.5))_(HCl)`
`CH_(3) COOH+NaOHrarrCH_(3)COONa+H_(2)O`
`20M"MOLE"20m"mole""SALT of weak acid weak base give basic solution"`.
23.

Magnesium is a valuable, light weight metal used as a structural material as well as in alloy hatteries and in chemical s . Although magnesium is plentiful in Earth s maire found in the sea water after sodium). There is about 1.3 8 of magnesium in every kilogram of se water. The process for obtaining magnesium from en water employs all three types of reaction Le precipitation, acid-base, and redox reactions Acid-base reaction involves reaction between :

Answer»

`MgCO_(3) and HCL`
`Mg(OH)_(2) and H_(2)SO_(4)`
`Mg(OH)_(2) and HCl`
`MgCO_(3) and H_(2) SO_(4)`

SOLUTION :REACTION between HCl and `Mg(OH)_(2)` is acid base reaction.
24.

Magnesium is a valuable, light weight metal used as a structural material as well as in all batteries and in chemical synthesis. Although magnesium is plentiful in carth crust, it is ma found in the sea water after sedium. There is about 1.38 of magnesium in every kilogram of water. The process for obtaining magnesium from se water employs all three types of reach le... precipitation acid-hase and redor racions. Electron is an alloy of

Answer»

Magnesium
Sodium
Alluminium
Manganese

Solution :ELECTRON is an alloy of Mg and its COMPOSITION is `95%+4.5% ZN +0.5 % Cu`
25.

Magnesium is a valuable, light weight metal used as a structural material as well as in all batteries and in chemical synthesis. Although magnesium is plentiful in carth crust, it is ma found in the sea water after sedium. There is about 1.38 of magnesium in every kilogram of water. The process for obtaining magnesium from se water employs all three types of reach le... precipitation acid-hase and redor racions. Redox reaction takes place in the extraction of Me

Answer»

In the ELECTROLYTIC cell when fuse `MgCl_(2)` is subjected to electrolysis
when fused `MgCO_(3)` is heated
when fused `MgCO_(3)`is strongly heated
none of the above

Solution :In the electrolytic cell, when fusd `MgCl_(2)` is subjected to electrlysis
At Anode `2CI^(-) to Cl_(2) +2e^(-)` (Oxidation) : At CATHODE `:MG^(2+)+2e^(-) to Mg` (Reduction)
26.

Magnesium has polarizing power closer to that of:

Answer»

Li
Na
K
Cs

Answer :A
27.

Magnesium cation has polarising power close to that of :

Answer»

`LI^(+)`
`NA^(+)`
`K^(+)`
`CS^(+)`

ANSWER :A
28.

Magnesium can displace:

Answer»

Cs
Cu
Rb
K

Answer :B
29.

Magnesium burns in CO_2 to form:

Answer»

MGO and CO
`MgCO_3`
MgO and C
`MgO_2`

ANSWER :C
30.

Magnesium burns in CO_(2) to form

Answer»

`MgO` and C
`MgCO_(3)`
`MgO_(2)`
`MgO` and `CO`

ANSWER :A
31.

Magnesium burns in air to give

Answer»

MGO
`Mg_(3)N_(2)`
`MgCO_(3)`
MgO and `Mg_(3)N_(2)` both

Solution :`2MG + O_(2) to 2MgO`
`3Mg + N_(2) to Mg_(3) N_(2)`
32.

Magnesium burns in air to give :

Answer»

MgO
`Mg_(3)N_(2)`
`MgCO_(3)`
`MgOandMg_(3)N_(2)`

ANSWER :D
33.

Magnesium allylide is _____, which on treatment with water gives _____

Answer»

`Mg_(3)C_(2) to ` ALLYLENE
`Mg_(2)C_(3) to`PROPYNE
`Mg_(3)C_(2) to ` Acetyline
`Mg_(2)C to ` Methane

Answer :B
34.

Magnesite (Magnesium carbonate) is calcined to obtain magnesia, which is used to make refractory bricks. Write the decomposition reaction.

Answer»

Solution :Magnesite is a carbonate of magnesium . Magnesite when heated at `800^@C` to `100^@C` at the `CO_2` CONTENT in it driven off. The residue so obtained is known as CALCINED magnesite.
`underset(("Magnesite"))(MgCO_3)OVERSET(800^@C" to "1000^@C)rarrunderset(("Magnesia"))(MGO)+CO_2uarr`
35.

Magnesite is calcined to give ……..

Answer»

SOLUTION :MAGNESIA
36.

Magnesite is:

Answer»

`MgCl_2`
`MgCO_3`
MGO
`MgSO_3`

ANSWER :B
37.

Magnesite is ________.

Answer»

MAGNESIUM oxide
Magnesium carbonate
Magnesium sulphate
Magnesium chloride

Answer :B
38.

Magnesia is:

Answer»

MGO
`CuSO_4`
`FeSO_4`
`MgSO_4`

ANSWER :A
39.

Magnalium contains aluminium and :

Answer»

Cu
MG
Cu ,Mg,NI and Sn
Cu, Ni and Mg

Answer :B
40.

Magenta is

Answer»

ALKALINE phenolphthalein
Methyl red
p-rosaniline HYDROCHLORIDE
Red litmus

Solution :p-rosanline hydrochloride.

It is USED for the IDENTIFICATION of ALDEHYDES.
41.

Maganetic separtion is used for increasing concentration of the:

Answer»

HORN silver
Calcite
Haemarite
Magnetite

Answer :C
42.

Macromolecular colloid is a -

Answer»

STARCH sol
sulphur sol
gelatin sol
micelle

Answer :B
43.

Magenta is :

Answer»

<P>ALKALINE phenolphthalein
Red LITMUS
p- ROSANILINE hydrochloride
Methyl red

Answer :C
44.

Mac Arthur process is used for :

Answer»

Ag
Fe
Cl
`O_2`

ANSWER :C
45.

Mac Arthur Forrest process is used for the extraction of ...............ores :

Answer»

CU
AG
Au
Pt.

Answer :C
46.

Mac Arthur and Forest cyanide process in used in the extraction of:

Answer»

Cu
Ag and Au
Fe
Cr

Answer :B
47.

Ma reacts with RBr best in

Answer»

`C_(2)H_(5)OC_(2)H_(5)`
`C_(2)H_(5)OCH_(3)`
`C_(6)H_(5)N(CH_(3))_(2)`
Equally in all the three

Solution :ALTHOUGH all the three compounds can be used for preparing Grignard REAGENTS, diethyl ether is considered as the bestbecause it provides electron pairs to Mg of the reagent fully for coordination, in caseof `C_(6)H_(5)0CH_(3) and C_(6)H_(5)N(CH_(3))_(2)` electron pair on 0 and N are partialy delocalised over the benzene and HENCE are less AVAILABLE for coordination with Mg.
48.

M^(3+) ion of the first transition series metal 'M' has a magnetic moment 1.73 BM. The atomic number of the metal 'M' is

Answer»

21
24
29
22

Answer :D
49.

M^(+)X^(–)has fccstructure with octahedral voids. Anion has radius of 300 pm. The ideal radius of cation will be :

Answer»

`0.414xx300`
`0732xx300`
`0.155xx300`
`0.225xx300`

ANSWER :A
50.

^^_(m) of 0.05 M weak electrolyte is "50 Sm"^(2)mol^(-1),0^(@) of it is "440 Sm"^(2)" mol"^(-1). Calculate alpha (degree of dissociation) of the electrolyte.

Answer»

Solution :Degree of dissociation of an electrolyte is GIVEN by
`ALPHA=(^^_(m))/(^^_(m)^(@))`
`"Given :"^^_(m)="50 sm"^(2)" mol"^(-1)`
`^^_(m)^(@)="440 sm"^(2)" mol"^(-1)`
`"conc "=0.05m`
`alpha=(50)/(440)(cancel(sm^(2)))/(cancel(sm^(2)))(cancel(mol^(-1)))/(cancel(mol^(-1)))`
`alpha=0.