Chapter 11

The compound $\mathrm{\Lambda }$ on heating gives a colourless gas and residuc which dissolves in water to give B. When cxcess of ${\mathrm{CO}}_2$ is passed into $\mathrm{B}$ and gently heated, $\mathrm{\Lambda }$ is formed. The compound $\mathrm{\Lambda }$ is (1) ${\mathrm{CaSO}}_{4}2{\mathrm{II}}_2\mathrm{O}$ (2) ${\mathrm{Na}}_2{\mathrm{CO}}_3$ (3) ${\mathrm{CaCO}}_3$ (4) ${\mathrm{K}}_2{\mathrm{CO}}_3$

A certain metal is present in the soil, plants, bones, egg shells, sea shells and coral. It is also used to remove oxygen from molten steel and its hydroxide is used to detect ${\mathrm{CO}}_2$. The metal is (1) $\mathrm{Mg}$ (2) $\mathrm{\Lambda }1$ (3) $\mathrm{Ca}$ (4) $\mathrm{Na}$

Which of the following statements is falsc? (1) Strontium decomposes water readily than beryllium. (2) Barium carbonate decomposes at a higher temperature than calcium carbonate. (3) Barium hydroxide is more soluble in water than magnesium hydroxide. (4) Barium hydroxide is less basic than magnesium hydroxide.

The electronegativity of aluminium is similar to that of (1) Barium (2) Beryllium (3) Calcium (4) Strontium

Both Be and Al become passive on reaction with conc. ${\mathrm{HNO}}_3$ because (1) they are non-reactive metals (2) of the non-reactive nature of the acid (3) of the formation of inert layer of oxide on the surface of metals (4) none of these

Which of the following statements is not correct? (1) Be like Al does not dissolve in alkalies. (2) Oxides of both Be and Al are amphoteric. (3) ${\mathrm{BeC}}_2$ like ${\mathrm{Al}}_4{\mathrm{C}}_3$ is covalent. (4) Burning of lime stone containing more than $10\mathrm{\%}$ aluminium silicates gives hydraulic mortar.

Beryllium differs from rest of the members of its family (II A group) in many ways. The reason for this is its (1) small size and high electronegativity. (2) small size and low electronegativity. (3) large size and lower ionization energy. (4) larger size and large ionic radius.

Milk of magnesia used as a medicine for treating indigestion is a substance that (1) helps in disintegration of food products leading to their metabolism (2) combines with gastric hydrochloric acid thereby enhancing the latter's efficiency (3) improves the enzymatic activities inside the stomach (4) neutralizes excess acidity, providing a buffered medium inside the stomach

The mixture of ${\mathrm{MgCl}}_2$ and $\mathrm{MgO}$ is called (1) Sorrel's cement (2) Mixed salt (3) Portland cement (4) Magnesium oxychloride

Epsom salt on strong heating gives (1) anhydrous salt (2) $\mathrm{MgO}+{\mathrm{SO}}_2+{\mathrm{O}}_2$ (3) $\mathrm{MgS}+{\mathrm{O}}_2$ (4) $\mathrm{Mg}{\mathrm{SO}}_3+{\mathrm{O}}_2$