Barium hydroxide, Ba(OH)2, is a strong base used in inorganic and organic reactions. Fig. 2.1 shows a reaction scheme involving Ba(OH)2. [Figure 2.1]

1. (a)(i)State the variation in solubilities of group 2 hydroxides.[1]
2. (a)(ii)State what is observed in reaction 1.[1]
3. (a)(iii)Suggest a reactant for reaction 2.[1]
4. (a)(iv)Identify A.[1]
5. (a)(v)Ba(OH)2 is made by the reaction of Ba with water. Write an equation for this reaction.[1]
6. (b)(i)The mineral barytocalcite contains both BaCO3 and CaCO3. Both compounds decompose on heating. State which compound decomposes first when barytocalcite is heated. Explain your answer.[1]
7. (b)(ii)Construct an equation for the complete thermal decomposition of barytocalcite. The formula of barytocalcite is BaCa(CO3)2. BaCa(CO3)2[1]
8. (c)Ba(OH)2 is used to hydrolyse organic compounds. Fig. 2.2 shows the reaction of B with Ba(OH)2, followed by acidification. Draw the structures of the organic products of the process shown in Fig. 2.2. [Figure 2.2][3]

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