What is the formula for magnesium chloride? Review of Formula Writing…
A positively charged ion is called a cation. A negatively charged atom is called an anion. So in an iconic compound the metal is the cation and the non-metal is the anion.
Some metals form more than one type of ion [can have more than 1 type of charge] We show the charge with a Roman numeral in brackets: Cu + … copper (I) Cu 2+ … copper (II)
What is the name for Fe 2 O 3 ?
Naming Multivalent Metals What is the name for Fe 2 O 3 ? Net charge has to be zero so… O 2- x 3 = -6 Fe ?+ X 2 = + 6 6/2 = 3 …so the charge on Fe is 3+ Answer: iron (III) oxide
What is the formula for chromium (III) oxide ? Cr 3+ Cl - Cr +3 x 1 = +3 Cr -1 x 3 = -3Net Charge = 0 Final Answer = CrCl3