What is the melting point of sulfur (in $K$)?

About $.......\, \%$ impurity remains in alumina obtained by Bayer's method. (in $\%$)

What are the constituent elements of brass?

Which method is used to collect $H_2$ gas in a gas jar in the laboratory?

What type of oxide is aluminium oxide $(Al_2O_3)$?

$(a)$ List two differences between calcination and roasting in tabular form.
$(b)$ Which method will you use to reduce the following? Explain by giving a suitable example.
$(i)$ Oxides of less reactive metals.
$(ii)$ Oxides of moderately reactive metals.
$(iii)$ Oxides of highly reactive metals.