Iron is extracted from magnetite by reduction with

In the extraction of iron,the reaction which occurs at $900-1500 \ K$ in the blast furnace is:

The reaction for obtaining the metal $(M)$ from its oxide $(M_{2}O_{3})$ ore is given by
$M_{2}O_{3(s)} + 2 Al(\ell) \xrightarrow{\text{Heat}} Al_{2}O_{3}(\ell) + 2 M_{(s)}$, $(s = \text{solid}, \ell = \text{liquid})$
In this case, $M$ is

When silica is present as an impurity in an ore,a/an ........ flux is required.

Which of the following pair of ores cannot be converted into corresponding metals by pyrometallurgy?

The flux added in the extraction of iron is