The correct statement regarding the given Ellingham diagram is

Which one of the following statements is incorrect

$Al _{2} O _{3}$ was leached with alkali to get $X$. The solution of $X$ on passing of gas $Y$, forms $Z . X$ $Y$ and $Z$ respectively are

Give the correct order of initials $T$ or $F$ for following statements. Use $T$ if statement is true and $F$ if it is false.

$(i)$ $Cu$ metal is extracted from its sulphide ore by reduction of $Cu_2O$ with $FeS.$

$(ii)$ An ore of Tin containing $FeCrO_4$ is concentrated by magnetic separation method.

$(iii)$ Auto reduction process is used in the extraction of $Cu\, \& \,Hg.$

$(iv)$ Cassiterite and Rutile are oxide ores of the metals.

Sodium thiosulphate is used in photography to :-