I remember grading the naming test a few years ago. The student started out decently. But the longer she went, the more convoluted the thoughts in her brain got. I wish I had a picture of her final answer. So I will summarize it here.
Cr(HCO3)3 was chromate monohydrogen carbonidic acid (III)
The poor thing. Her brain was an alphabet soup of bits and pieces of naming conventions. I thought I had done a pretty good job teaching the unit. Some kids got 100% on the test. It was so easy and obvious. But to some, I was speaking in what appeared to be an ancient dead language with hieroglyphics. So, I started to think about how to simplify it down. How to create a flow to the logic of naming. Below are some of the tips and "Kochisms" that I have started using that have improved performance, particularly in my struggling grade-level kids.
Use a visual flow chart.
Before we even start learning the naming conventions, I hand out this flow chart. It gives them some questions to ask themselves to quickly identify what type of compound, and therefore what naming convention to use.
The flow chart is color coded by naming convention. Red is acid, green is molecular and blue is ionic. I chose to separate the acids first to create some mental space between the acids and the ionic compounds, which obviously have some overlap. This gives them a reason to follow a naming convention. Not a guess. By the way, you can download the flow chart on our resources page.
2. Use silly sounding mnemonic devices.
I will give a couple of mnemonics for the acid naming conventions.
My ride has hydraulics. (I wish I could remember the citation for this one. It’s on YouTube. Somewhere.)
Ous is ite. As in slang for “we are alright.” (Trust me, a student came up with this one and thinks he is so funny. But funny works.)
When differentiating between molecular and ionic compounds, the primary evidence I have them look for is what types of elements make up the compound. Is it a nonmetal + nonmetal? We say made of nons.
Nons use mons. This means if you have two nonmetals you will use the “mons” or the prefixes (mon, di, tri, etc) to identify how many of each atom there are. It sounds dumb to say out loud, but nons use mons does really help.
3. Help them recognize polyatomic ions.
I do not mean to open a can of worms here, but I do have my students memorize a selection of polyatomic ions. I feel that if they memorize the common ones at first, they will become more efficient at writing equations in the future. They don’t have to stop to look up every subscript and every charge every time. After they take their polyatomic ion quiz (which doesn’t affect their overall grade to a high degree) they are allowed to use the reference table on the back of their periodic table. That way they can be fast and efficient, but also have the backup of a reference if needed.
A question that commonly comes up from the students is, “How do I know how many oxygens are in an ‘ate’ versus an ‘ite’.” The kids just want to know the pattern. So, I tell them up front.
THERE IS NO PATTERN.
While I do explain that “ates” will have more oxygen that the “ites” some kids just need to hear out loud that there isn’t a pattern. Otherwise, they go crazy trying to create one. Here are a couple of little phrases that I use to help them.
It’s ite to be little. (again, slang for alright. And again, painfully awkward when I say it out loud trying to sound cool)
If you ate more you will get bigger. These two try to differentiate the larger number of oxygens in ates from the smaller number in ites.
4. Tell them exactly where to find the ions.
Within the alphabet soup of all the naming conventions, the kids can get lost knowing where to reference things. If you can give them a physical location to look as well as a mental one, they will be better off. The way that I try to help them is to have them constantly show me on the periodic table the location of the “ides”. Which is in the nonmetal corner. Over and over and over I will have the class point to where sulfide is at on the table. Where is bromide? Where is selenide? Front, top, left side of the periodic table.
Then I will have them point to the “ates” and the “ites”. For us, those are on the back of the periodic table. (By the way, Montana Tech University will send you free periodic tables for all your students as well as one for the wall. Just ask, and I’m sure they will hook you up.) Where is sulfate? Back of the table. Where is permanganate? Back of the table. Train them physically where to look and they will start to mentally recognize the patterns as well.
5. Practice naming using all the conventions.
As I was reviewing some of the homework that I assigned this year, I found an error. The top of page one said “Ionic Compound Naming”. Page two was molecular. Page three was acids. This is changing next year. When the kids practiced problems that included all three conventions without identifying which one to use, the students became more engaged on making naming decisions. They had to use the skills outlined on the flowchart to decide what to do. This engages their brain to a higher degree and their retention will be higher over the long haul.
6. Have some grace.
Often the naming chapter is near the beginning of “real chemistry”. They are starting up the steep incline of learning in front of them. Naming is going to be the foundation of balancing equations which is the foundation of stoichiometry which is the foundation of chemistry. We have to help them win at this stage in the game. Spend more practice time. Slow the pace of the class down even though this is “easy”. I just handed back tests today and one of my students sat with a blank defeated look on his face. He had worked so hard. He had watched the extra videos. He had done the extra practice. He had met me at lunch and after school. And his score sucked. And so next week I will spend all my lunches and after school with him. He will try and fail and learn and try again. And then maybe we will get a win. But I specifically sought him out today to tell him how much the work he already put in mattered. It will pay off. I believe in your work. I believe in you. I’m hoping that will be what it takes to get him over the hump.
After all the alphabet soup starts to clear in their head and they know that the teacher is on their side, maybe they will decide that chemistry is ite after all. (I’m so sorry. I couldn’t help it.)
Are you looking for a quick way to have your students practice writing ionic formulas? Do you want it to be fast? Do you want it to take little effort and setup? Check out CHeMgO! It is the classroom bingo game that grows with your students. You choose the level of challenge and they get lots of competitive reps. Check out this video to hear a little more. Pre-orders are going on right now for 20% off!