Analytical ChemistryHard
Question
Which of the following metal salts gives a red and opaque borax bead in the reducing flame (in cold) ?
Options
A.Ni
B.Fe
C.Cu
D.Mn
Solution
Na2B4O7 
2NaBO2 + B2O3
CuO + B2O3
Cu(BO2)2
2Cu(BO2)2 + 4NaBO2 + 2C
2Cu (red and opaque) + 2Na2B4O7 + 2CO ↑
2NaBO2 + B2O3CuO + B2O3
Cu(BO2)22Cu(BO2)2 + 4NaBO2 + 2C
2Cu (red and opaque) + 2Na2B4O7 + 2CO ↑Create a free account to view solution
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