Question

what product is formed when 1-butyne is treated with excess br2 in ccl4?select answer from the options below1,2-dibromobutene1,1-dibromobutane2,2-dibromobutane1,2-dibromobutane1,1,2,2-tetrabromobutane

Answer 1

The product formed when 1-butyne reacts with excess bromine in CCl4 is 1,1,2,2-tetrabromobutane, which occurs through a halogen addition reaction where all the carbon atoms from the original triple bond are saturated with bromine atoms.

Step-by-step explanation:

When 1-butyne is treated with excess Br2 in CCl4, the product formed is 1,1,2,2-tetrabromobutane.

1-butyne is an alkyne with a triple bond between the first and second carbon atoms. In the presence of excess bromine, the triple bond reacts to form a tetra-substituted alkane. Each carbon atom involved in the triple bond gets two bromine atoms attached - one bromine atom adds to each carbon in the initial step to form a 1,2-dibromobutene, then another addition of bromine happens to achieve the final product, 1,1,2,2-tetrabromobutane, where both carbons previously involved in the triple bond are now each bonded to two bromine atoms.

Answer 2

The product formed when 1-butyne is treated with excess Br2 in CCl4 is 1,1,2,2-tetrabromobutane, resulting from a stepwise addition of bromine to the triple bond.

Step-by-step explanation:

When 1-butyne is treated with excess Br2 in CCl4, the product formed is 1,1,2,2-tetrabromobutane. This happens because the triple bond in 1-butyne reacts with the excess bromine in a stepwise addition reaction to add four bromine atoms to the molecule, resulting in the tetrabrominated product. Each step of the reaction involves the addition of two bromine atoms across the triple bond, first creating a brominated alkene intermediate, which then reacts with another equivalent of bromine to give the final product, 1,1,2,2-tetrabromobutane.