Multiple Choice
What is the name given to the regular pattern in which an ionic compound is arranged?
3. Chemical Reactions
Naming Ionic Compounds
Struggling with General Chemistry?
Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
Which of the following is the correct chemical formula for zinc(II) iodide?
A
Zn2I2
B
Zn2I
C
ZnI
D
ZnI2
Verified step by step guidance1
Identify the charge on the zinc ion in zinc(II) iodide. The Roman numeral II indicates that zinc has a charge of +2, so the ion is Zn^{2+}.
Determine the charge on the iodide ion. Iodide is the ion form of iodine and carries a charge of -1, so the ion is I^{-}.
To write the correct chemical formula, balance the total positive and negative charges so the compound is electrically neutral. Since Zn^{2+} has a +2 charge and I^{-} has a -1 charge, you need two iodide ions to balance one zinc ion.
Write the formula by placing the zinc ion first followed by the iodide ions, using subscripts to indicate the number of each ion. This gives ZnI_{2}.
Verify that the formula ZnI_{2} is neutral: one Zn^{2+} ion (+2) and two I^{-} ions (2 × -1 = -2) sum to zero charge, confirming the correct formula.
2:11mWatch next
Master Ionic Compounds Naming with a bite sized video explanation from Jules
Start learningRelated Videos
Related Practice
Naming Ionic Compounds practice set
Problem sets built by lead tutorsExpert video explanations