Which of the following statements are correct ? (A) AsH3> PH3 > NH3 (decreasing order of basic strength) (B) H2O> NH3 > PH3 (decreasing order of boiling point) (C) NO > NO2 > N2O3 (decreasing oxidation state of nitrogen) (D) H4P2O6 > H4P2O5 > H3PO4 (decreasing oxidation state of phosphorus) (E) H2O > H2S > H2Se (decreasing thermal stability) Choose the correct answer from the options given below:
1
(A) and (B) only
2
(C) and (D) only
3
(B) and (E) only
4
(D) and (E) only
Official Solution
Correct Option: (3)
The correct option is (C) : (B) and (E) only
02
PYQ 2023
medium
chemistryID: cuet-ug-
KMnO4 + H2SO4 + X → MnSO4 + K2SO4 + H2O + CO2 Identify X :
1
C6H12O6
2
C2H2O4
3
C2H6
4
C2H8
Official Solution
Correct Option: (2)
The correct option is (B) :C2H2O4.
03
PYQ 2023
medium
chemistryID: cuet-ug-
is named as:
1
Dichloridobis (triphenyl phosphine) nickel (II)
2
Nickel chlorido bis (triphenyl phosphine)
3
Diphenyl phosphine Nickel (II) chloride
4
Dichlorobis (Diphenyl phosphine) Nickel (II)
Official Solution
Correct Option: (1)
The correct option is (A) : Dichloridobis (triphenyl phosphine) nickel (II)
04
PYQ 2023
medium
chemistryID: cuet-ug-
What is basicity of
1
1
2
2
3
3
4
5
Official Solution
Correct Option: (3)
The correct option is(C):3
05
PYQ 2023
medium
chemistryID: cuet-ug-
The value of magnetic moment for is:
1
4.4 BM
2
4.5 BM
3
4.6 BM
4
4.9 BM
Official Solution
Correct Option: (4)
The correct option is (D): 4.9 BM
06
PYQ 2023
medium
chemistryID: cuet-ug-
The least basic hydroxide amongst the following would be:-
1
2
3
4
Official Solution
Correct Option: (4)
The correct option is (D): Yb (OH)3 (Z=70)
07
PYQ 2023
medium
chemistryID: cuet-ug-
[Co(NH3)4Cl(NO2)]Cl will show: A. Solvate isomerism B. Linkage isomerism C. Coordination isomerism D. Ionisation isomerism Choose the correct answer from the options given below :
1
A and B only
2
B and C only
3
B and D only
4
C and D only
Official Solution
Correct Option: (3)
The correct option is (C) :B and D only.
08
PYQ 2023
medium
chemistryID: cuet-ug-
Match List-I with List-II.
List-I
List-II
(A)
Molecular solid
(I)
CaF2
(B)
Ionic solid
(II)
Cu
(C)
Metallic Solid
(III)
CCl4
(D)
Covalent solid
(IV)
SiC
Choose the correct answer from the options given below:
1
(А)-(І), (В)-(III), (C)-(II), (D)-(IV)
2
(A)-(III), (B)-(IV), (C)-(II), (D)-(I)
3
(A)-(IV), (B)-(I), (C)-(II), (D)-(III)
4
(A)-(III), (B)-(I), (C)-(II), (D)-(IV)
Official Solution
Correct Option: (4)
The correct option is (D) : (A)-(III), (B)-(I), (C)-(II), (D)-(IV)
09
PYQ 2023
medium
chemistryID: cuet-ug-
Match List-I with List-II.
List-I
List-II
(A)
XeO3
(I)
sp3d2
(B)
XeF6
(II)
sp3d3
(C)
XeOF4
(III)
sp3d
(D)
XeOF2
(IV)
sp3
Choose the correct answer from the options given below:
1
(A)-(IV), (B)-(II), (C)-(I), (D)-(III)
2
(A)-(I), (B)-(II), (C)-(III), (D)-(IV)
3
(A)-(III), (B)-(I), (C)-(II), (D)-(IV)
4
(A)-(I), (B)-(II), (C)-(IV), (D)-(III)
Official Solution
Correct Option: (1)
The correct option is (A) : (A)-(IV), (B)-(II), (C)-(I), (D)-(III)
10
PYQ 2023
medium
chemistryID: cuet-ug-
Atoms of element B form hcp lattice and those of the element A occupy of octahedral voids. What is the formula of the compound formed by the element A and B?
1
2
3
AB
4
Official Solution
Correct Option: (2)
The correct option is(B):
11
PYQ 2023
medium
chemistryID: cuet-ug-
Grignard reagent should be prepared under anhydrous condition because
1
carbon - Mg bond is not highly polar
2
Mg-X bond is essentially covalent
3
It reacts with proton of water to form HX
4
It reacts with H2O to form alkane
Official Solution
Correct Option: (4)
The correct option is(D):It reacts with H2O to form alkane
12
PYQ 2023
medium
chemistryID: cuet-ug-
Amongst the following ions which one has the highest magnetic moment value?
1
K[Co(CO)4]
2
K4[Mn(CN)6]
3
[Fe(H2O)6]2+
4
[Cr(H2O)6]3+
Official Solution
Correct Option: (3)
The correct option is (C) : [Fe(H2O)6]2+
13
PYQ 2023
medium
chemistryID: cuet-ug-
Assuming [NiCl4] as Complex-A and [Ni(CO)4] as Complex-B, choose the correct statement. (At.No. of Ni is 28.)
1
State of hybridization of Ni in complex-A is dsp2 and in complex-B is sp3.
2
Complex-A is paramagnetic and complex-B is diamagnetic
3
Oxidation state of Ni in both complexes is +2
4
CO is a weaker ligand than CT
Official Solution
Correct Option: (2)
The correct option is (B) : Complex-A is paramagnetic and complex-B is diamagnetic
14
PYQ 2023
medium
chemistryID: cuet-ug-
Which of the following ionic species has the greatest proton affinity to form stable compound?
1
2
3
4
Official Solution
Correct Option: (3)
The correct option is(C):
15
PYQ 2023
medium
chemistryID: cuet-ug-
In which of the following molecules carbon atom marked with asterix (*) is a stereocentre or Chiral centre ?
1
Image
2
Image
3
Image
4
Image
Official Solution
Correct Option: (1)
The correct option is (A) : Image
16
PYQ 2023
medium
chemistryID: cuet-ug-
Which among the following solids is an example of ionic solid ?
1
Fe, Cu, Ag, Mg
2
NaCl, MgO, ZnS
3
Ar, CCl4
4
SiO2, SiC
Official Solution
Correct Option: (2)
The correct option is (B) : NaCl, MgO, ZnS
17
PYQ 2024
medium
chemistryID: cuet-ug-
Consider the following compounds:Arrange these compounds in the increasing order of rate of hydrolysis:
1
(B) < (D) < (C) < (A)
2
(B) < (D) < (A) < (C)
3
(D) < (B) < (A) < (C)
4
(A) < (D) < (B) < (C)
Official Solution
Correct Option: (2)
To determine the increasing order of rate of hydrolysis for the given compounds, we should consider the stability of the leaving groups in each compound. Hydrolysis is generally facilitated when the leaving group is more stable. Hence, the criteria depend on: 1) The ability of the leaving group to stabilize the negative charge once it departs. 2) The other substituents present which might have an electronic effect (like resonance or inductive effects) on the leaving group.
Compound B: Has a strong leaving group compared to others, making it undergo hydrolysis at a slower rate.
Compound D: Slightly better leaving group than compound B but still not as good as others, resulting in a faster hydrolysis than B but slower than A and C.
Compound A: Has a better leaving group than compounds B and D but not as effective as the leaving group in compound C.
Compound C: Likely to have the best leaving group (perhaps due to resonance stabilization), leading to the fastest rate of hydrolysis.
Thus, the correct order of increasing rate of hydrolysis is: (B) < (D) < (A) < (C).
18
PYQ 2024
medium
chemistryID: cuet-ug-
What is the IUPAC name of [Pt(NH3)2Cl(NO2)]?
1
Diamminechloridonitrito-N-platinum(II)
2
Diamminechloridenitrito-N-platinum(III)
3
Diamminechloridonitrito-O-platinum(II)
4
Diammonia chloridonitrito-N-platinum(II)
Official Solution
Correct Option: (1)
To determine the IUPAC name for the complex [Pt(NH3)2Cl(NO2)], we need to follow the rules for naming coordination compounds:
Identify the ligands and their order: The ligands are listed alphabetically in the compound's name, ignoring any prefixes. Here, we have two ligands: Ammine (NH3) and Chlorido (Cl) along with Nitrito, which is a bidentate ligand and specifically bound via the nitrogen atom in this context, hence Nitrito-N.
Determine the oxidation state of the metal: Platinum (Pt) is the central metal in this complex. The ammonia (NH3) ligands are neutral, chlorido (Cl) is -1, and nitrito-N (NO2) is -1. The overall charge for the molecule is neutral, thus: Ptn+(2×0)+(1×-1)+(1×-1)=0, giving us n = +2 for platinum. Hence, it is platinum(II).
Name the complex: Combine the ligand names with the metal in the following manner: "Diamminechloridonitrito-N-platinum(II)". Note the use of "Diammine" for two amine groups, "chlorido" for Cl, and "nitrito-N" indicating the nitrogen atom as the donor atom.
Thus, the correct IUPAC name is: Diamminechloridonitrito-N-platinum(II).
19
PYQ 2024
medium
chemistryID: cuet-ug-
The central atom/ions in coordination compounds are referred to as:
1
Lewis base
2
Lewis acid
3
Bronsted acid
4
Bronsted base
Official Solution
Correct Option: (2)
The central atom/ion in coordination compounds is referred to as a Lewis acid.
To understand why this is the correct term, we need to explore some chemical concepts:
Lewis Acid: A Lewis acid is defined as a chemical species that can accept an electron pair. In coordination chemistry, the central atom or ion acts as a Lewis acid because it can accept electron pairs from ligands, which are Lewis bases that donate electron pairs.
Coordination Compounds: These compounds consist of a central atom/ion surrounded by molecules or ions called ligands. The central metal ion attracts these ligands to form a stable structure due to its ability to accept electron pairs.
Example: In a coordination compound like [Cu(NH3)4]2+, copper (Cu) is the central ion, and it acts as a Lewis acid by accepting electron pairs from ammonia (NH3) molecules.
Therefore, the central atom/ions in coordination compounds are best described as Lewis acids.
20
PYQ 2024
easy
chemistryID: cuet-ug-
Which of the following compounds will be repelled when placed in an external magnetic field?
1
2
3
4
Official Solution
Correct Option: (3)
To determine which compound will be repelled in an external magnetic field, we need to assess the magnetic properties of each compound. Generally, compounds are diamagnetic or paramagnetic:
Diamagnetic compounds have no unpaired electrons and are repelled by a magnetic field.
Paramagnetic compounds have unpaired electrons and are attracted by a magnetic field.
Let's analyze the given options:
: The central atom is , which usually has unpaired electrons, making it paramagnetic.
: The central atom is , known for having unpaired electrons, making it paramagnetic.
: The central atom is . Cadmium typically does not have unpaired electrons in its common oxidation state, making it diamagnetic.
: The central atom is , which typically has unpaired electrons, making it paramagnetic.
Based on the above analysis, is the compound that will be repelled by an external magnetic field due to its diamagnetic nature.
21
PYQ 2024
medium
chemistryID: cuet-ug-
What is the co-ordination number of metal in [Fe(C O ) ] ?
1
Two
2
Three
3
Six
4
Four
Official Solution
Correct Option: (3)
The coordination number of a metal ion in a complex refers to the number of ligand donor atoms bonded to the metal. In the complex [Fe(C2O4)3]3-, the ligand is oxalate (C2O42-), which is a bidentate ligand. This means each oxalate ligand can form two bonds with the metal ion.
Let's calculate:
The complex contains three oxalate ligands: [Fe(C2O4)3]3-.
Each oxalate ligand coordinates with two donor sites.
Therefore, the total number of coordination sites is 3 ligands × 2 donor sites per ligand = 6.
Thus, the coordination number of the metal (Fe) in the complex is six.
22
PYQ 2024
easy
chemistryID: cuet-ug-
The correct order of increasing boiling points of the following compounds is: Pentan-1-ol, n-Butane, Pentanal, Ethoxyethane
1
Ethoxyethane, Pentanal, n-Butane, Pentan-1-ol
2
Pentanal, n-Butane, Ethoxyethane, Pentan-1-ol
3
n-Butane, Pentanal, Ethoxyethane, Pentan-1-ol
4
n-Butane, Ethoxyethane, Pentanal, Pentan-1-ol
Official Solution
Correct Option: (4)
To determine the correct order of increasing boiling points among n-Butane, Ethoxyethane (Diethyl ether), Pentanal, and Pentan-1-ol, we have to consider intermolecular forces which include Van der Waals forces, dipole-dipole interactions, and hydrogen bonding.
n-Butane: It is an alkane with weak Van der Waals forces and no significant dipole moments or hydrogen bonding, resulting in a low boiling point.
Ethoxyethane (Diethyl ether): It has stronger Van der Waals forces than n-butane and can participate in dipole-dipole interactions because of its ether group, leading to a higher boiling point compared to n-butane.
Pentanal: As an aldehyde, it possesses a polar carbonyl group, which means it exhibits stronger dipole-dipole interactions compared to ethoxyethane, thus having a higher boiling point than ethoxyethane.
Pentan-1-ol: This compound has the ability to form hydrogen bonds due to the presence of a hydroxyl group (-OH), which drastically increases its boiling point compared to the others.
Thus, the order of increasing boiling points is: n-Butane, Ethoxyethane, Pentanal, Pentan-1-ol.
23
PYQ 2025
easy
chemistryID: cuet-ug-
The coordination number of the central metal ion in is:
1
4
2
6
3
2
4
3
Official Solution
Correct Option: (2)
Step 1: Understand the coordination number. The coordination number is the number of ligand atoms directly bonded to the central metal ion. Step 2: Analyze the complex .} Here, Fe is surrounded by 6 cyanide ( ) ligands. Each CN⁻ is a monodentate ligand (donates one electron pair), so the coordination number is 6.