Which one of the following metals will give blue ash when its salt is heated with $Na_2CO_3$ solid and $Co(NO_3)_2$ on a charcoal piece?

Given below are two statements:
Statement $I$: Colourless cupric metaborate is reduced to cuprous metaborate in a luminous flame.
Statement $II$: Cuprous metaborate is obtained by heating boric anhydride and copper sulphate in a non-luminous flame.
In the light of the above statements,choose the most appropriate answer from the options given below.

Which of the following gives the chromyl chloride test?

Assign $A, B, C, D$ from the given type of reaction.
$Na_2CO_3 + KNO_3 \longrightarrow$ No reaction

What is a fusion mixture?

Which of the following cations cannot give a borax bead test?