The correct formula of permanganic acid is
$HMn{O_4}$
$HMn{O_5}$
${H_2}Mn{O_4}$
${H_2}Mn{O_3}$
Which of the following alloys contain only $Cu $ and $Zn$
Passing $H_2S$ gas into a mixture of $Mn^{+2}, Ni^{+2}, Cu^{+2}$ and $Hg^{2+}$ ions in an acidified aqueous solution precipitates
The form of iron having the highest carbon content is
$Fe,$ $Co$ and $Ni$ have valuable catalytic properties in process involving