Which of the following imparts green colour to the glass
$C{u_2}O$
$CdS$
$Mn{O_2}$
$C{r_2}{O_3}$
Which of the following is wrongly matched
Which of the following pair both compounds have no exsistance
Mark the variety of iron which has highest melting point
$(a)$ Transition metals can act as catalysts because these can change their oxidation state. How does $Fe(III)$ catalyse the reaction between iodide and persulphate ions ?
$(b)$ Mention any three processes where transition metals act as catalysts.
Which of the following graph is correct representation between atomic number $(Z)$ and magnetic moment of $d-block$ elements? [Outer electronic configuration : $(n -1)d^x\, ns^{1\, or \,2}$]