By QB365 on 31 Dec, 2022
QB365 provides a detailed and simple solution for every Possible Questions in Class 12 Chemistry Subject - Important 1 Mark MCQ's, English Medium. It will help Students to get more practice questions, Students can Practice these question papers in addition to score best marks.
12th Standard
Chemistry
Answer all the following questions.
Which one of the following reaction represents calcinations?
\(2Zn+{ O }_{ 2 }\rightarrow 2ZnO\)
\(2ZnS+3O_{ 2 }\rightarrow 2ZnO+2SO_{ 2 }\)
\(MgCO_{ 3 }\rightarrow MgO+CO_{ 2 }\)
Both (a) and (c)
Zinc is obtained from ZnO by________.
Carbon reduction
Reduction using silver
Electrochemical process
Acid leaching
Which of the following is not true with respect to Ellingham diagram?
Free energy changes follow a straight line. Deviation occurs when there is a phase change.
The graph for the formation of CO2 is a straight line almost parallel to free energy axis.
Negative slope of CO shows that it becomes more stable with increase in temperature.
Positive slope of metal oxides shows that their stabilities decrease with increase in temperature.
In diborane, the number of electrons that accounts for banana bonds is ________.
six
two
four
three
The repeating unit in silicone is_______.
SiO2
The compound that is used in nuclear reactors as protective shields and control rods is _________.
Metal borides
metal oxides
Metal carbonates
metal carbide
An element belongs to group 15 and 3rd period of the periodic table, its electronic configuration would be_______.
1s2 2s2 2p4
1s2 2s2 2p3
1s2 2s2 2p6 3s2 3p2
1s2 2s2 2p6 3s2 3p3
Among the following the correct order of acidity is ________.
HClO2 < HClO < HClO3 < HClO4
HClO4 < HClO2 < HClO < HClO3
HClO3 < HClO4 < HClO2 < HClO
HClO < HClO2 < HClO3 < HClO4
Among the transition metals of 3d series, the one that has highest negative \(\left( \frac { M^{ 2+ } }{ M } \right) \) standard electrode potential is _______.
Ti
Cu
Mn
Zn
How many moles of I2 are liberated when 1 mole of potassium dichromate react with potassium iodide?
1
2
3
4
Which one of the following is not correct?
La(OH)3 is less basic than Lu(OH)3
In lanthanoid series ionic radius of Ln3+ ions decreases
La is actually an element of transition metal series rather than lanthanide series
Atomic radii of Zr and Hf are same because of lanthanide contract
As per IUPAC guidelines, the name of the complex [Co(en)2(ONO)Cl]Cl is _______.
chloro bis ethylenediamine nitrocobalt(III) chloride
chloridobis(ethane-1, 2-diamine)nitro K-O Cobaltate(III) chloride
chloridobis(ethane-1, 2-diammine)nitrito K-O Cobalt(II) chloride
chloridobis(ethane-1, 2-diamine)nitrito K-O Cobalt(III) chloride
A complex in which the oxidation number of the metal is zero is_______.
K4[Fe(CN)6]
[Fe(CN)3(NH3)3]
[Fe(CO)5]
both (b) and (c)
In calcium fluoride, having the fluorite structure the coordination number of Ca2+ ion and F- Ion are ________.
4 and 2
6 and 6
8 and 4
4 and 8
If ‘a’ is the length of the side of the cube, the distance between the body centered atom and one corner atom in the cube will be_________.
\(\left( \cfrac { 2 }{ \sqrt { 3 } } \right) a\)
\(\left( \cfrac { 4 }{ \sqrt { 3 } } \right) a\)
\(\left( \cfrac { \sqrt { 3 } }{ 4 } \right) a\)
\(\left( \cfrac { \sqrt { 3 } }{ 2 } \right) a\)
Among the following graphs showing variation of rate constant with temperature (T) for a reaction, the one that exhibits Arrhenius behavior over the entire temperature range is _______.
both (b) and (c)
For the reaction, 2NH3 ⟶ N2 + 3H2, if \(\frac { -d[NH_{ 3 }] }{ dt } \) = k1[NH3], \(\frac { d[N_{ 2 }] }{ dt } =k_{ 2 }[NH_{ 3 }],\frac { d[{ H }_{ 2 }] }{ dt } \)= k3[NH3] then the relation between k1, k2 and k3 is _________.
k1 = k2 = k3
k1 = 3k2 = 2k3
1.5k1 = 3k2 = k3
2k1 = k2 = 3k3
In a first order reaction x ⟶ y; if k is the rate constant and the initial concentration of the reactant x is 0.1M, then, the half life is_____.
\(\left( \frac { \log2 }{ k } \right) \)
\(\left( \frac { 0.693 }{ (0.1)k } \right) \)
\(\left( \frac { In2 }{ k } \right) \)
none of these
The solubility of BaSO4 in water is 2.42 × 10-3gL-1 at 298K. The value of its solubility product(Ksp) will be (Given molar mass of BaSO4 =233g mol-1)
1.08 × 10-14mol2L-2
1.08 × 10-12mol2L-2
1.08 × 10-10mol2L-2
1.08 × 10-8mol2L-2
Which of the following relation is correct for degree of hydrolysis of ammonium acetate?
\(h=\sqrt { \frac { { K }_{ h } }{ C } } \)
\(h=\sqrt { \frac { { K }_{ a } }{ K_b } } \)
\(h=\sqrt { \frac { { K }_{ w } }{ { K }_{ a }.{ K }_{ b } } } \)
\(h=\sqrt { \frac { { { K }_{ a }.{ K }_{ b } } }{ { K }_{ w } } } \)
The button cell used is watches function as follows
Zn (s) + Ag2O (s) + H2O (l) ⇌ 2Ag (s) + Zn2+ (aq) + 2OH-(aq) the half cell potentials are Ag2O (s) + H2O (l) + 2e- → 2Ag (s) + 2OH- (aq) Eo = 34V and Zn (s) → Zn2+ (aq) + 2e− E0 = 0.76V . The cell potential will be_______.
0.84V
1.34V
1.10V
0.42V
During electrolysis of molten sodium chloride, the time required to produce 0.1mole of chlorine gas using a current of 3A is _____.
55 minutes
107.2 minutes
220 minutes
330 minutes
Consider the change in oxidation state of Bromine corresponding to different emf values as shown in the diagram below:
\({ BrO }_{ 4 }^{ - }\overset { 1.82V }{ \longrightarrow } { BrO }_{ 3 }^{ - }\overset { 1.5V }{ \longrightarrow } HBrO\overset { 1.595v }{ \longrightarrow } { Br }_{ 2 }\overset { 1.0652V }{ \longrightarrow } Br^{ - }\)
Then the species undergoing disproportional is
Br2
BrO4-
BrO-3
HBrO
Hair cream is _____.
gel
emulsion
solid sol
sol.
Collodion is a 4% solution of which one of the following compounds in alcohol – ether mixture?
Nitroglycerine
Cellulose acetate
Glycoldinitrate
Nitrocellulose
On which of the following properties does the coagulating power of an ion depend?
Both magnitude and sign of the charge on the ion.
Size of the ion alone
the magnitude of the charge on the ion alone
the sign of charge on the ion alone.
The X is _______.
None of these
on treatment with Con H2SO4, predominately gives______.
On reacting with neutral ferric chloride, phenol gives ______.
red colour
violet colour
dark green colour
no colouration.
Predict the product Z in the following series of reactions Ethanoic acid \(\overset { { PCI }_{ 5 } }{ \longrightarrow } X\overset { { C }_{ 6 }{ H }_{ 6 } }{ \underset { Anhydrous \ AlCI }-_{3}{ \longrightarrow } } Y\overset { 1){ CH }_{ 3 }MgBr }{ \underset { II){ H }_{ 3 }{ O }^{ + } }{ \longrightarrow } } Z.\)
(CH3)2 C(OH)C6H5
CH3CH(OH)C6H5
CH3CH(OH)CH2- CH3
The IUPAC name of
but – 3- enoicacid
but – 1- ene-4-oic acid
but – 2- ene-1-oic acid
but -3-ene-1-oicacid
In which of the following reactions new carbon – carbon bond is not formed?
Aldol condensation
Friedel craft reaction
Kolbe’s reaction
Wolf kishner reduction
CH3CH2 Br \(\overset { aqNaOH }{ \underset { \Delta }{ \longrightarrow } } A\overset { { KMnO }_{ 4 }{ /H }^{ + } }{ \underset { \Delta }{ \longrightarrow } } B\overset { { NH }_{ 3 } }{ \underset { \Delta }{ \longrightarrow } } C\overset { { Br }_{ 2 }/NaOH }{ \longrightarrow } D\) D' is________.
bromomethane
α - bromo sodium acetate
methanamine
acetamide
_______.
H3PO2 and H2O
H+/H2O
HgSO4/H2SO4
Cu2Cl2
Identify X in the sequence give below
The correct statement regarding RNA and DNA respectively is ______.
the sugar component in RNA is an arabinos and the sugar component in DNA is ribose
the sugar component in RNA is 2’-deoxyribose and the sugar component in DNA is arabinose
the sugar component in RNA is an arabinose and the sugar component in DNA is 2’-deoxyribose
the sugar component in RNA is ribose and the sugar component in DNA is 2’-deoxyribose
Which one of the following structures represents nylon 6,6 polymer?
Which is the monomer of neoprene in the following?
\(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{C} \equiv \mathrm{CH}\)
\(\mathrm{CH}_{2}=\mathrm{CH}-\mathrm{CH}=\mathrm{CH}_{2}\)
Among the following, one does not belong to calcination, Pick the odd one out.
\({ PBCO }_{ 3 }\overset { \Delta }{ \longrightarrow } PBO+{ CO }_{ 2 }\uparrow \)
\({ CaCo }_{ 3 }\overset { \Delta }{ \longrightarrow } Cao+{ CO }_{ 2 }\uparrow \)
\(PbS{ O }_{ 3 }\overset { \Delta }{ \rightarrow } PbO+{ 2SO }_{ 2 }\uparrow \)
\({ ZnCO }_{ 3 }\overset { \Delta }{ \rightarrow } ZnO+{ CO }_{ 2 }\uparrow \)
SiO44- ion has ____ geometry.
Triangular
Tetrahedral
Linear
Pentagonal bipyramidal
The C60 molecule is called as_________ because of its structure.
buck minster fullerene
bucky balls
diamond
both (a) & (b)
Pick the wrong one among the following
F2 - Yellow
Br2 - Red
Cl2 - Colourless
I2- Violet
The general electronic configuration of 4f series of elements can be written as ________.
[Xe]4f2-14 5d0-46s2
[Xe]4f2-145d0-46s1
[Xe] 4f1-14506s1
[Xe]4f2-145d0-46s1
Among the following complexes the one which shows zero crystal field stabilisation energy is _______.
[Mn(H2O)6]3+
[Fe(H2O)6]3+
[CO(H2O)6]2+
[CO(H2O)6]3+
Identify, the geometrical isomer of platinum complex with the ligands NH3 & Cl
Choose the correct option
i & ii
ii & iii
i & iii
ii & iv
The empty space between the shaded balls and hollow balls as shown in the diagram is called, _______.
Hexagonal void
Octahedral void
Tetrahedral void
Double triangular void
It is a 2 steps reaction, step 1 is slower than step 2
It is a 2 steps reaction, step 2 is slower than step 1.
Single step reaction where B is a activated complex
Single step reaction in which B is a reaction intermediate.
Concentration is expressed in?
\(\frac { number\ of\ moles/litre }{ time\ in\ sec } \)
\(\frac { time\ in\ sec }{ number\ of\ moles/litre } \)
\(\frac { number\ of\ moles/litre }{ volume } \)
\(\frac { volume }{ number\ of\ moles/litre } \)
The relationship between degree of dissociation of a weak acid and its dissociation constant in a very dilute solution is _______.
Ka = α2C
Ka = \(\frac{α^2C}{(1+α)}\)
Ka = \(\frac{α^2}{(1+α)C}\)
Ka = \(\frac{α}{C(1+α)}\)
Using the data given below find out the strongest reducing agent ______.
\({ E }_{ { Cr }_{ 2 }{ O }_{ 7 }^{ 2- } }^{ o }{ Cr }^{ 3+ }=1.33V{ ,E }_{ { Cl }_{ 2 }{ / }{ Cl }^{ - } }^{ o }=1.36V\)
\({ E }_{ { Mn }O_{ 4 }^{ - } }^{ 0 }/{ Mn }^{ 2+ }=1.51V,{ E }_{ { Cr }^{ 3+ }/Cr }^{ o }=-0.74V\)
Cr
Cr3+
Cl-
Mn2+
Answers
\(MgCO_{ 3 }\rightarrow MgO+CO_{ 2 }\)
Carbon reduction
The graph for the formation of CO2 is a straight line almost parallel to free energy axis.
four
Metal borides
1s2 2s2 2p6 3s2 3p3
HClO < HClO2 < HClO3 < HClO4
Ti
3
La(OH)3 is less basic than Lu(OH)3
chloridobis(ethane-1, 2-diamine)nitrito K-O Cobalt(III) chloride
[Fe(CO)5]
8 and 4
\(\left( \cfrac { \sqrt { 3 } }{ 2 } \right) a\)
1.5k1 = 3k2 = k3
\(\left( \frac { In2 }{ k } \right) \)
1.08 × 10-10mol2L-2
\(h=\sqrt { \frac { { K }_{ w } }{ { K }_{ a }.{ K }_{ b } } } \)
1.10V
107.2 minutes
HBrO
emulsion
Nitrocellulose
Both magnitude and sign of the charge on the ion.
violet colour
(CH3)2 C(OH)C6H5
but – 3- enoicacid
Wolf kishner reduction
methanamine
H3PO2 and H2O
the sugar component in RNA is ribose and the sugar component in DNA is 2’-deoxyribose
\(PbS{ O }_{ 3 }\overset { \Delta }{ \rightarrow } PbO+{ 2SO }_{ 2 }\uparrow \)
Tetrahedral
both (a) & (b)
Cl2 - Colourless
[Xe]4f2-14 5d0-46s2
[Fe(H2O)6]3+
i & ii
Octahedral void
It is a 2 steps reaction, step 1 is slower than step 2
\(\frac { number\ of\ moles/litre }{ time\ in\ sec } \)
Ka = α2C
Cr