CHAPTER 10 (Group 2)

Which of the following physical properties decreases when going down group 2 ?

• First ionisation energy
• Atomic radius
• Number of electron shells
• Number of valence electrons

Which of the following is not the physical property shown?

• Reactivity
• First ionisation energy
• Electronegativity
• Melting point

The melting point of Group 2 elements is higher than the melting point of the corresponding Group 1 elements because the Group 2 elements…

• Have higher ionisation energies
• Have a larger atomic
• Have a more compact metallic crystal lattice
• Uses two valence electrons for metallic bonding

The standard reduction electrode potentials of several Group 2 elements are as shown below. Be²⁺+2e⁻➝Be E ͒= -1.85V Mg²⁺+2e⁻➝Mg E ͒= -2.38V Ca²⁺+2e⁻➝Ca E ͒ = -2.87V Ba²⁺+2e⁻➝Ba E ͒= -2.90V Which of the following cannot be deduced from the above information?

• Only beryllium can form complex ions.
• Barium is the strongest reducing agent.
• The reactivity of the metals increases down the group.
• The metals become more increasingly electropositive.

Which of the following equations correctly represents the reaction when calcium nitrate is heated strongly

• 2Ca(NO₃)₂→2CaO+4NO₂+O₂
• Ca(NO₃)₂→Ca(NO₂)₂+O₂
• Ca(NO₃)₂→CaO+N₂O+2O₂
• 2Ca(NO₃)₂→2CaO+4NO+3O₂

Which of following statements best explain why the group 2 carbonates become increasingly less stable towards heat when going up the group ?

• The polarisation power of the metal cation toward the carbonate anion increases
• The ionic bond in the carbonate compounds become increasingly weaker .
• The metals become increasingly electropositive.
• The radius of the metal cation decreases

When 4.80g magnesium nitrate sample was heated strongly, the final mass of the residue is 1.00g . What is the percentage purity of the sample? [RAM: N=14; O=16; Mg=24]

• 0.771
• 81.4%
• 0.868
• 0.925

A 4.0g sample of calcium carbonate contaminated by calcium oxide, reacts completely with excess hydrochloric acid to evolve 500cm3 of carbon dioxide at s.t.p. What is the percentage by mass of calcium carbonate in the sample? [ARC=12, O=16, Ca=40; 1 mole of gas occupies a volume of 24dm3 at s.t.p.]

• 0.52
• 0.48
• 0.585
• 61.5%

Which of the following statements is true about calcium, strontium, and barium?

• All the metals liberate hydrogen gas when added to cold water.
• All the metal hydroxides are not soluble in water.
• All the oxides are amphoteric.
• All the metals are stronger reducing agents than Group 1 metals.

Which of the following oxides can dissolve in both sodium hydroxide and dilute hydrochloric acid ?

• BeO
• BaO
• MgO
• CaO