What is the formula for cupric cyanide?
The formula for cupric cyanide is
The cupric ion (from the latin "cuprum", corresponding to
The cyanide ion has a charge of
All ionic compounds' charges must add up to the net charge, so the number of positive ions and negative ions must be such that the total positive charge plus the total negative charge equals the net charge.
Since the cupric ion has a charge of
Therefore, the formula for cupric cyanide contains one cupric ion and two cyanide ions, and the formula is
#"Cu"^(2+) + "2CN"^(-)# #rarr# #"Cu(CN)"_2#