2. Using 1-butyne as the starting material, write the necessary reactions to convert to the indicated products. (a) Butane (b) 1-Butene (c) 2,2-Dibromobutane (d) 2-Pentane 3. Show how 2-butyne can be converted into 2-butene. 4. Using propyne as the starting material, carry out the following reaction sequences to give the following products. (a) 2-Butyne (b) 2-Butene (c) 2-Bromobutane (d) Pentane 5. How does one convert 1-pentene to 1-pentyne? 1-Bromobutane to 1-butyne? PROCEDURE Calcium carbide is added to water. This produces acetylene gas, which is then ignited. Observe the colour change in the beaker. H20 CaC2 Figure 1 12