Which metal is used in Wurtz synthesis?

The preparation of ethane by electrolysis of an aqueous solution of potassium acetate is called as:

Which of the following compounds is not obtained when a mixture of $CH_3Br$ and $C_2H_5Br$ is treated with sodium metal in the presence of dry ether?

When ethyl iodide and propyl iodide react with $Na$ in the presence of ether,they form

In the synthesis of sodium lauryl sulphate,lauryl alcohol is treated with $H_2SO_4$ to form lauryl hydrogen sulphate,which is then neutralized with $NaOH$. The structure of lauryl alcohol is $CH_3(CH_2)_nCH_2OH$. What is the value of '$n$'?

What does petroleum mainly consist of?