Limestone is present in the blast furnace production of iron in order to
$(I)$ provide a source of $CaO$
$(II)$ remove some impurities
$(III)$ supply $CO_2$

Tin is obtained from cassiterite by reduction with coke. Use the data given below to determine the minimum temperature (in $K$) at which the reduction of cassiterite by coke would take place.
At $298 \ K$: $\Delta_{f}H^{\circ}(SnO_{2(s)}) = -581.0 \ kJ \ mol^{-1}$,$\Delta_{f}H^{\circ}(CO_{2(g)}) = -394.0 \ kJ \ mol^{-1}$
$S^{\circ}(SnO_{2(s)}) = 56.0 \ J \ K^{-1} \ mol^{-1}$,$S^{\circ}(Sn_{(s)}) = 52.0 \ J \ K^{-1} \ mol^{-1}$
$S^{\circ}(C_{(s)}) = 6.0 \ J \ K^{-1} \ mol^{-1}$,$S^{\circ}(CO_{2(g)}) = 210.0 \ J \ K^{-1} \ mol^{-1}$
Assume that the enthalpies and the entropies are temperature independent.

The function of fluorspar $(CaF_2)$ in the electrolytic reduction of alumina $(Al_2O_3)$ dissolved in fused cryolite $(Na_3AlF_6)$ is

In the metallurgy of copper,metallic copper is finally formed in the furnace by the reactions:

Predict conditions under which $Al$ might be expected to reduce $MgO$.

Which of the following statements is/are correct based on the provided Ellingham diagram?