A Hydroxyl (-OH)
B Carbonyl (C=O)
C Carboxyl (-COOH)
D Amine (-NH2)
Explanation: Acetic acid (CH3COOH) contains the carboxyl group (-COOH), which is a combination of a carbonyl and a hydroxyl group on the same carbon.
A Tetrahedral
B Trigonal bipyramidal
C Square planar
D Octahedral
Explanation: sp3d hybridization produces five hybrid orbitals arranged in a trigonal bipyramidal geometry with bond angles of 90 and 120 degrees.
A 1 mole
B 2 moles
C 3 moles
D 4 moles
Explanation: From the balanced equation 2H2 + O2 -> 2H2O, 2 moles of H2 produce 2 moles of H2O.
A Na2O
B Al2O3
C MgO
D SO3
Explanation: Al2O3 is amphoteric because it reacts with both acids (forming Al3+ salts) and bases (forming aluminate AlO2- ions).
A [Ar] 3d6 4s2
B [Ar] 3d6
C [Ar] 3d5 4s1
D [Ar] 3d8
Explanation: Fe has configuration [Ar] 3d6 4s2. When forming Fe2+, two electrons are removed from 4s first, giving [Ar] 3d6.
Explanation: NH3 deviates most due to its strong intermolecular hydrogen bonding and larger molecular size compared to the nonpolar gases H2, He, and N2.
A 98 g/mol
B 49 g/mol
C 32.7 g/mol
D 196 g/mol
Explanation: H2SO4 is diprotic (donates 2 H+ ions). Equivalent weight = molar mass / n-factor = 98 / 2 = 49 g/mol.
A Period 2
B Period 3
C Period 4
D Period 5
Explanation: The d-block begins in Period 4 with scandium (Sc, Z=21), which has the first 3d electron: [Ar] 3d1 4s2.
A Linear
B Bent (V-shaped)
C Trigonal planar
D Tetrahedral
Explanation: SO2 has sp2 hybridization with one lone pair on sulfur, giving a bent (angular) molecular geometry with a bond angle of about 119 degrees.
Explanation: HF is the weakest hydrohalic acid because the strong H-F bond makes dissociation difficult, despite fluorine\'s high electronegativity.
Explanation: In the NaCl (rock salt) structure, each Na+ is surrounded by 6 Cl- ions and each Cl- by 6 Na+ ions, giving a coordination number of 6.
A Sodium metal
B Bromine water
C Sodium hydroxide
D Silver nitrate
Explanation: Bromine water (Br2 in water) decolorizes when added to unsaturated compounds (alkenes/alkynes) due to addition across the double/triple bond.
A 40%
B 6.67%
C 53.33%
D 33.33%
Explanation: Molar mass of glucose = 180 g/mol. Mass of 6 C atoms = 72 g. Percent C = (72/180) x 100 = 40%.
Explanation: Atomic radius increases down a group as new electron shells are added. Rb (Period 5) is the largest among these alkali metals.
Explanation: In O2, the MO configuration gives (bonding electrons - antibonding electrons)/2 = (10-6)/2 = 2.
A HCl + NaCl
B CH3COOH + CH3COONa
C NaOH + NaCl
D H2SO4 + Na2SO4
Explanation: A buffer consists of a weak acid (CH3COOH) and its conjugate base (CH3COO- from CH3COONa), which resists pH changes.
Explanation: C4H10 has two structural isomers: n-butane (straight chain) and isobutane (2-methylpropane, branched).
A sp3
B sp3d
C sp3d2
D d2sp3
Explanation: SF6 has sulfur bonded to 6 fluorine atoms with no lone pairs, requiring sp3d2 hybridization and octahedral geometry.
A Iron
B Copper
C Aluminum
D Zinc
Explanation: Aluminum is extracted from molten Al2O3 (dissolved in cryolite) by electrolysis in the Hall-Heroult process due to its high reactivity.
Explanation: Na2SO4 dissociates into 2Na+ and SO42-, producing 3 ions per formula unit, so i = 3.