[Dan]

Hint:

  acetone + HCl

[orgopete]

The question asks to identify the products and mechanism of the following reaction:
CH₃CH=C(CN)₂ + H₂O → C₂H₄O + C₃H₂N₂
The problem is on a sheet about addition to a C=C bond. I can't work out how you get two products with those molecular formulae. If anyone could help it would be much appreciated!

If C3H2N3 is malononitrile, then the starting material can be formed if the arrow for the above reaction is reversed.

[camptzak]

water acts as a nucleophile and attacks the carbon attached to the methyl and the hydrogen. The anion on the carbon with cyano groups then grabs a proton.
A lone pair on the alcohol group comes down and kicks off the carbon with the two cyanide groups and a hydrogen attached. The anion grabs another proton forming your C₃H₂N₂.
Also you have your acetylaldehyde.

The acetylaldehyde and the hydrate would be in equilibrium with eachother.

wont the cyano groups move to carboxylic acid groups in water?