A sample of $6.40 g$ of the compound $HC \equiv C - CH X_{2} - CH (OH) - CH X_{2} - COOH$ (molar mass $128 g mo l^{- 1}$ ) is treated with excess $CH X_{3} MgBr$ in dry ether. Assume that only reactions with active (acidic) hydrogen occur, that each such hydrogen liberates one mole of $CH X_{4}$ , and that there is no addition to the triple bond. Find the number of moles of $CH X_{4}$ evolved (two decimal places).

Numerical answer type, answer in mol, tolerance 0.005.

Answer: 0.15 mol

Active hydrogens: the terminal alkyne C-H, the alcoholic O-H and the carboxylic O-H, so 3 per molecule. Moles of compound =

6.40/128 = 0.050

. Moles of

CH X_{4}

3 \times 0.05

0.15 mol