Question

Choose from the following list of substances, as of what matches the description given below:

[Acetylene gas, aqua fortis, coke, brass, barium chloride, bronze, platinum]

A gaseous hydrocarbon commonly used for welding purposes.

Answer 1

The compounds given in the question are:

Acetylene gas, aqua fortis, coke, brass, barium chloride, bronze, platinum

A gaseous hydrocarbon commonly used for welding purposes is:

Acetylene($CH\equiv CH$) is commonly used for welding purposes because the combustion of Acetylene gas($CH\equiv CH$) evolves a high amount of energy i.e. $-1300\mathrm{kJ}$ as it undergoes an exothermic reaction which is necessary for the welding.

The combustion reaction of Acetylene is given below:

$\underset{Acetylene}{2CH\equiv CH\left(g\right)}+\underset{Oxygen}{5O_2\left(g\right)}\to \underset{Carbondioxide}{4C{O}_2\left(g\right)}+\underset{Water}{2H_{2}O\left(aq\right)}$