Explanation

• sp-hybridization has 50% s-character, the highest among the given hybridization types.
• Greater s-character keeps the bonding electrons closer to the nucleus, generally resulting in a shorter bond length.
• The order of s-character is sp (50%) > sp² (33.3%) > sp³ (25%).
• Therefore, for comparable bonds between the same atoms, sp-hybridized bonds generally have the shortest bond length.

Last verified on 27-10-2026

Explanation

• Hydrogen sulphide (H₂S) dissolves in water and ionizes weakly, producing hydrogen ions (H⁺) and hydrosulphide ions (HS⁻).
• The added H⁺ ions shift the ionization equilibrium of sulphuric acid toward the unionized form, reducing its ionization due to the common-ion effect.
• The common-ion effect occurs when an ion already present in an equilibrium is added, suppressing further ionization of a weak electrolyte.

Last verified on 27-10-2026

Explanation

• Potassium chloride (KCl) is a strong electrolyte that dissociates almost completely into K⁺ and Cl⁻ ions in water.
• Potassium hydroxide (KOH) also dissociates completely, adding more K⁺ ions to the solution.

Last verified on 27-10-2026

Explanation

• A sodium atom produces a line spectrum when its electrons move between specific, quantized energy levels and emit or absorb photons of definite wavelengths.
• Each element has a characteristic line spectrum because its electrons have a unique set of energy levels.

Last verified on 27-10-2026

Explanation

• Hydrogen fluoride (HF) has a very high ionic character because fluorine is much more electronegative than hydrogen.
• Its dipole moment is approximately 1.82 debye (D), which is greater than that of hydrogen chloride (HCl), approximately 1.08 D, and hydrogen disulphide (H₂S), approximately 0.97 D.
• Dipole moment depends on both the magnitude of separated charges and the distance between them.
• HF has a particularly strong bond polarity due to the large electronegativity difference between hydrogen and fluorine.

Last verified on 27-10-2026

Explanation

• Sodium carbonate forms a basic solution in water because it is a salt of a strong base (NaOH) and a weak acid (H₂CO₃).
• Carbonate ions react with water to produce hydroxide ions (OH⁻), increasing the pH above 7.

Last verified on 27-10-2026

Explanation

• Chromium has atomic number 24, so it has 24 electrons.
• Its most stable electronic configuration is [Ar] 3d⁵ 4s¹.
• The half-filled 3d subshell (3d⁵) provides extra stability.

Last verified on 27-10-2026

Explanation

• The electronic configuration 4d¹⁰ 5s² 5p⁵ belongs to iodine (I), which is a halogen with seven valence electrons.
• Iodine can gain or lose electrons during chemical reactions, so it participates in oxidation-reduction (redox) reactions.
• In a redox reaction, oxidation and reduction occur together through the transfer of electrons or changes in oxidation states.

Last verified on 27-10-2026

Explanation

• Racing cars are made more stable by lowering their centre of gravity, which reduces the tendency to topple while turning.
• A lower centre of gravity helps the car maintain balance when experiencing outward effects during sharp turns.
• Racing cars also use wide tyres and carefully designed suspension systems to improve grip and stability.

Last verified on 27-10-2026

Explanation