How does water move on its own concentration gradient?

A+b→2c when the reaction begins, the researcher records that the rate of reaction is such that 1 mole of a is consumed per minute. after making changes to the reaction, the researcher notes that 2 moles of a are consumed per minute. what change could the researcher have made to effect this change?

In the reaction between a crushed antacid tablet and vinegar what gas is emitted

Is this correct if not can u correct me