<Tr> <Td> Conversion of alcohols to ethers </Td> <Td> 2 R--OH → R--O--R + H O </Td> <Td> </Td> </Tr> <Tr> <Td> Conversion of alcohols to alkenes </Td> <Td> R--CH CHOH--R → R--CH = CH--R + H O </Td> <Td> for example the conversion of glycerol to acrolein: <Dl> <Dd> </Dd> </Dl> <P> or the dehydration of 2 - methyl - 1 - cyclohexanol to (mainly) 1 - methylcyclohexene </P> <Dl> <Dd> </Dd> </Dl> </Td> </Tr> <P> or the dehydration of 2 - methyl - 1 - cyclohexanol to (mainly) 1 - methylcyclohexene </P> <Tr> <Td> Conversion of carboxylic acids to acid anhydrides </Td> <Td> 2 RCOOH → (RCO) O + H O </Td> <Td> </Td> </Tr>

Describe the role of water in a dehydration reaction