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The hybridization of central atom in SO₃ is A sp B sp² C sp³ D sp³d Explanation Sulfur in SO₃ has three σ bonds and no lone pair on the central atom → trigonal planar geometry → sp² hybridization. Which molecule has zero lone pair on central atom A NH₃ B H₂O C BF₃ D…

The molecule having pyramidal shape is A BF₃ B NH₃ C CO₂ D BeCl₂ Explanation NH₃ has 3 bond pairs and 1 lone pair on N (AX₃E). Electron geometry is tetrahedral but molecular shape is trigonal pyramidal. Which molecule is expected to have square pyramidal geometry A SF₆ B BrF₅ C PF₅ D XeF₄ Explanation…

Which bond is formed due to overlap of orbitals along internuclear axis A Pi bond B Sigma bond C Hydrogen bond D Ionic bond Explanation Sigma (σ) bond is formed by head-on (axial) overlap of orbitals along the internuclear axis. Which overlap results in formation of a π bond A s–s overlap B s–p overlap…

The bond formed by complete transfer of electrons is A Ionic bond B Covalent bond C Metallic bond D Hydrogen bond Explanation In ionic bonding, one atom transfers electron(s) to another forming cations and anions held by electrostatic attraction. Which factor increases ionic character in a bond A Small electronegativity difference B Large electronegativity difference…

The number of moles of H atoms present in 18 g of water is A 0.5 mol B 1.0 mol C 2.0 mol D 4.0 mol Explanation 18 g H₂O = 1 mol H₂O. Each mole of water contains 2 moles of H atoms → 2 mol H atoms. The mass of 3.01 × 10²³…

The number of significant figures in 0.004560 is A 3 B 4 C 5 D 6 Explanation Leading zeros are not significant. Significant figures are 4, 5, 6, and trailing zero after decimal → total 4. Which law states that mass is neither created nor destroyed in a chemical reaction A Law of multiple proportions…

The mass of 0.5 mole of CO₂ is A 11 g B 22 g C 44 g D 88 g Explanation Molar mass of CO₂ = 44 g/mol. For 0.5 mol, mass = 0.5×44=220.5 \times 44 = 220.5×44=22 g. At STP, 11.2 L of an ideal gas contains A 0.25 mol B 0.5 mol C…