Problem 24
Which of the following statements is false? (1) Beryllium forms covalent compounds due to small size and high charge of the \(\mathrm{Be}^{2+}\) ion. (2) The maximum coordination number of beryllium is \(\mathbf{s i x}\). (3) Beryllium salts are extensively hydrolyzed. (4) Beryllium can form complexes due to its small size.
Problem 29
Alkaline earth metals form carbides of the type \(\overline{M C}_{2}\). But \(\mathrm{MgC}_{2}\) on heating converts into \(\mathrm{X}\), which on hydrolysis give (1) Methane (2) Acetylene (3) Propyne (4) Ethane
Problem 31
The hydration energies of Group 2 ions are four to five times greater than that of the group 1 ions. This is due to their (1) smallcr size and increascd nuclear charge (2) greater size and decreased nuclear charge (3) smaller size and decreased nuclear charge (4) grcater size and increased nuclear charge
Problem 32
Which of the following statements is wrong? (1) Elements of Group 2 are good conductors of electricity and heat. (2) Compounds of Group 2 elements are diamagnetic in nature. (3) The salts of Group 2 elements are more heavily hydrated than those of elements of group 1 . (4) Element of Group 2 are more electropositive than Group 1 elements.
Problem 33
Which of the following is least ionic chloride? (1) \(\mathrm{BeCl}_{2}\) (2) \(\mathrm{MgCl}_{2}\) (3) \(\mathrm{CaCl}_{2}\) (4) \(\mathrm{SrCl}_{2}\)
Problem 35
True peroxide is (1) \(\mathrm{NO}_{2}\) (2) \(\mathrm{MnO}_{2}\) (3) \(\mathrm{BaO}_{2}\) (4) \(\mathrm{SO}_{2}\)
Problem 36
The correct order regarding the solubility of alkaline carth metal halide in water is (1) \(\mathrm{BeCl}_{2}>\mathrm{MgCl}_{2}>\mathrm{CaCl}_{2}>\mathrm{SrCl}_{2}>\mathrm{BaC} \mathrm{l}_{2}\) (2) \(\mathrm{MgCl}_{2}>\mathrm{CaCl}_{2}>\mathrm{BeCl}_{2}>\mathrm{BaCl}_{2}>\mathrm{SrCl}_{2}\) (3) \(\mathrm{BaCl}_{2}>\mathrm{MgCl}_{2}>\mathrm{CaCl}_{2}>\mathrm{BeCl}_{2}>\mathrm{SrCl}_{2}\) (4) \(\mathrm{CaCl}_{2}>\mathrm{MgCl}_{2}>\mathrm{SrCl}_{2}>\mathrm{BaCl}_{2}>\mathrm{BeCl}_{2}\)
Problem 38
The correct order of increasing ionic character is (1) \(\mathrm{BeCl}_{2}>\mathrm{MgCl}_{2}>\mathrm{CaCl}_{2}>\mathrm{BaCl}_{2}\) (2) \(\mathrm{BeCl}_{2}>\mathrm{MgCl}_{2}>\mathrm{BaCl}_{2}>\mathrm{CaCl}_{2}\) (3) \(\mathrm{BeCl}_{2}<\mathrm{MgCl}_{2}<\mathrm{CaCl}_{2}<\mathrm{BaCl}_{2}\) (4) \(\mathrm{BeCl}_{2}<\mathrm{CaCl}_{2}<\mathrm{MgCl}_{2}<\mathrm{BeCl}_{2}\)
Problem 40
Which among the following statements is correct? (1) In the solid state \(\mathrm{BeCl}_{2}\) has a polymcric chain structure and contains three centred bonds. (2) In the vapour state \(\mathrm{BeCl}_{2}\) exists as a dimer. (3) \(\mathrm{BeCl}_{2}\) is a covalent compound soluble in organic solvents. (4) \(\Lambda\) ll are correct.
Problem 41
Which of the following statements is correct? (1) No peroxide of beryllium is known is on date. (2) The ease with which peroxide is formed decreases with increase in the size of atom. (3) \(\mathrm{BaO}_{2}\) is prepared by passing air over \(\mathrm{BaO}\) at \(500^{\circ} \mathrm{C}\) (4) Peroxide of \(\mathrm{Mg}, \mathrm{Ca}, \mathrm{Sr}\) and \(\mathrm{Ba}\) are white ionic solids containing \(\mathbf{O}_{2}^{2-}\) ion.
