BANK OF MCQs

Download Group–I A 1.       Li-Na-K-Rb-Cs-Fr 2.       Group first members are called alkali metals since they form oxides and hydroxides which combine with water to produce alkaline solution. 3.       Li-Na and K are safe to save in school lab and rest are violently reactive. 4.       They are softer than other metals and can cut with knife. 5.       These metals are lighter than other elements and having low melting point, boiling point and density. Atomic and physical properties 6.       Down the group; ·         Atomic radius → Increases ·         Density → Decreases ·         Ionization energy → Decreases ·         Electronegativity → Decreases ·         M.P and B.P → Decreases 7.       Potassium is lighter than sodium. Trend in reactivity with water 8.       Excluding Lithium, which reacts slower than al the other elements of group-I. 9.       The reactivity of group-I follow the values of electrode potential. Reaction with oxygen 10.

Physical and atomic properties 1.       Na – Mg – Al – Si – P – S – Cl – Ar 2.       Metallic radii for sodium, magnesium and aluminium. 3.       Covalent radii for silicon, phosphorus , sulphur and chlorine 4.       Van der wall radii for Argon. 5.       Ionization energy increase from left to right, exception→ Al and S. 6.       Electronegativity increases from left to right, exception → Ar 7.       Sodium , magnesium and aluminium are best conductors. 8.       Silicon is semiconductor. 9.       Phosphorus, sulphur, chlorine and argon are non-conductors. 10. Melting point and boiling point values increase up to Al and then decreases. Reaction of 3 rd period elements with water, oxygen and chlorine 11. Magnesium and aluminium form layers when reacting with water. 12. Sodium undergoes exothermically reaction with cold water. 13. Magnesium reacts slowly with cold water and burn in stea