Everything Science Grade 12

CHAPTER 1. ORGANICMOLECULES 1.7

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(1.) 01nv (2.) 01nw (3.) 01nx

The Alkynes ESCS

In the alkynes, there is at least one triple bond between two of the carbon atoms. They
are unsaturated compounds and are therefore highly reactive. Their general formula is
CnH 2 n− 2. The simplest alkyne isethyne (figure 1.19), also known as acetylene. Many
of the alkynes are usedto synthesise other chemical products.

FACT

The raw materials that

are needed to make

acetylene are calcium

carbonate and coal.

An important use of

acetylene is in oxyacety-

lene gas welding. The

fuel gas burns with oxy-

gen in a torch. An in-

credibly high heat is pro-

duced, and this is hot

enough to melt metal.

H C C H

Figure 1.19: Ethyne (acetylene)

Naming the alkynes ESCT

The same rules will apply as for the alkanes andalkenes, except that thesuffix of the
name will now be -yne.

Example 8: Naming the alkynes

QUESTION

Give the IUPAC name for the following compound: