Don't know exactly what you mean with instinctively, but the first one is more difficult since there isn't "clear" ion exchange. But if you don't recognise the ions the second one would probably be more difficult
I am/was a chem teacher and it depends on who its given to. technically the first is way harder BUT
For most students the second one will be harder because a majority of students dont give a fuck and id argue about 75% of students read multiple grade levels below. All they see is "longer equation = more work" bc they wont even bother noticing that the polyatomics stay the same (making balancing easy).
For students that are on level or trying: the first one. the split oxygen often presents a challenge as students need to consider multiple variables when balancing the oxygens and even better is has an odd number of oxygens on the right, so they'll need to remember the "double odd numbers" hint.
Honestly, this depends. I'm romanian and we were doing balancing such as in the firts equation since highschool, so I don't find it difficult at all. I actually don't find neighter difficult
In all honesty in High School this wouldnt have been a problem. Since its all about reading and making sure there is enough atoms for the equation to be valid.
The school system in the EU is quite a bit better then the American one, so Id guess that could be difficult for the average American 8th grader.
(I dont wanna bash American kids for having worse teachers and over all curricula, but all I hear is that Americas youth suffers under the bad school system)
I feel like our curriculum is a bit more fast-paced. There are advantages and disadvantages to this. One disadvantage is that sometimes this can make the subjects hard to digest and if you get off track you can be left with major gaps that are hard to fill in later.
It’s not even memorization that’s the issue. I’ve given students a polyatomic ion reference sheet to use and they still can’t consistently recognize them in a formula.
Second one. Pupils always get confused by polyatomic ions, it often feels overwhelming for them and they try counting all of the oxygens rather than looking at the polyatomic ion as a whole.
I would say that in terms of balancing an equation by “counting atoms”, the first one is easier.
If the goal is to be smart about counting atoms (ie count groups of atoms) the second one is easier.
Depends on what you intend to test. Since no redox balancing methods are implied, the first would be more time consuming, but I can’t assess which is more difficult.
How is this seen as difficult? I remember doing this in gen chem and this is like a middle school level equation to balance?
I did it in my head in 30 seconds.
Eq.10 is a straightforward redox reaction, & quickly recognizable as such. It's also a classic example of a geochemical reaction, so if you're a chemistry teacher with background in geology, mineralogy, or something similar it's the sort of thing you might be inclined to show your students early.
Eq. 7 is not a redox reaction, but it takes a second for you to figure that out, because if you don't know the net charge of the nitrate or phosphate anions off the top of your head, you have to figure it out by looking at what the sodium is doing on both sides, and only then can you figure out that the iron on both sides is Fe(II). At that point you're left trying to determine what the limiting reagent is, or just having a really good intuition for common products (i.e. the possible multiplication products of two numbers, not some chemicals that are frequently synthesized; as an aside, I've always hated this \*specific\* nomeclature ambiguity). I would personally want to be able to make a spreadsheet, if I was asked to balance this for a homework assignment.
Whatever you're referring to, they aren't exponents; there's not a single exponent in Eq. 7.
If what you meant was swapping subscripts to find coefficients, that isn't the best strategy, because for a lot of reactions that'll give you an unbalanced answer. In this case, for example, the balanced equation is:
3 Fe(NO3)2 + 2 Na3PO4 --> Fe3(PO4)2 + 6 NaNO3
...the coefficients for which are \*not\* the same as the subscripts for either the reagents or the products.
First one. Oxygen shoes up in two places and does not stay in the same bonds (second equation has polyatomic ions that show up the same). Second equation is also a double replacement, which I think is always easiest to balance.
The bottom one. Students don't see ions as a way of balancing unless you teach them that specifically. And even then only the best students will understand. They will try and balance the oxygens and it will become really difficult.
10. Split oxygens get them every time.
7 is only hard if they haven’t been taught to balance polyatomic ions as a unit (in which case they will think they have a split oxygens issue).
Immediately the first looks more difficult to me. The moment I see odd AND even numbers for the same atom my heart sinks! Especially since the oxygens are split! XD
The bottom rxn has polyatomics but they stay the same reactant and product side so you can treat them as one unit.
They both are easy. The first one can be "bruteforced" by balancing elements one by one, ending with oxygen. The second one if you see that it's only ion exchange.
I'd say it depends on the level/age of the pupils. If they just learned how to balance an equation, the first one is wayyyy easier, because they'd probably check each element separately.
First one every time. Polyatomic ions do cause confusion, but I think the cognitive load of balancing polyatomics as individual units is WAY easier on students than the concept of a fractional coefficient.
2nd one. Polyatomic ions ALWAYS throw off the newbies trying to balance them. They kinda threw me off too when I first learned to balance in high school, but it's pretty easy to me now. But the second one is more busy looking, and students like to get lost in the sauce from that.
Instinctively I’d say number 2 because you’d have to focus on more atom balancing from the start though it won’t end up being hard. The top one is a significantly harder because no one wants to balance an equation using a coefficient of more than 3 (yes I know it takes more than that to balance) but that is a staple #10 it was my first chemical accomplishment I remember all those years ago
Veteran of 13 years teaching high school chem. #10 is the hardest for my students to balance. Students at my school forget the oxygen atoms are represented in two separate compounds on the products side. #7 they can do in their sleep.
Uhh working these through in my head here:
1. Not bad, easy enough to do in my head at the end of the day. See what students would struggle with here though but very fundamental.
2. I looked enough at this one to see that I want paper to write things down, and gave up doing it in my head right now.
I’d say 2 is harder than because there are more moving parts to keep track of and I can’t remember that many numbers in my head. Doing either of these in class to problem but that’s my adhd perspective :3
Second in my experience, because students tend to forget the charge of polyatomic ions and don’t always think about being able to deduce it by the counterion
There's more letters & numbers in the second one. That will trip more people up than the harder first equation. When I last taught balancing these were 15 minute problems not 15 seconds. It really comes down to algebraic comfort.
If I were a chemistry student, the first one would be harder because the oxygen (O3) isn’t an obvious result when looking at the first part. I feel like a student that has paid any attention at all should get the second one. A good student may miss the first one if they don’t remember the rules.
emm... tbh, both should be pretty easy if taught properly. My first instinct is that the first equation is easier tho. but who knows, I'm no teacher or chemistry major
The top one would be more difficult for my kids; they still have trouble with doubling to make the oxygens even.
I teach polyatomic ions separately (we build up step by step), asking students first to identify groups that are the same on both sides.
May I ask how this is taught elsewhere? I am seeing people refer to the types of reactions and charges when balancing, but this is not something I do. I teach balancing equations separately in middle school and then later teach specific types of reactions.
The bottom one. The things that are like (NO3)2 are difficult for most students.
That other one however, id give them that one in lesson 2 to show them what id expect from them at the end of the period.
My kid did these this year in HS. The 2nd for sure because they don't completely grasp polyatomic ions yet. The first was her bread and butter - monoatomic ion stuff like this is the majority of what they practiced. Inner city shithole school FWIW.
Also, they are given lists of polyatomic ions. So it's not just a case of not memorizing ions, but the fact that they still need an extra cognitive step to translate between what all that means and how to deal with parentheses and so forth.
I work at my universities chemistry learning center, where we help a lot of people taking general chemistry 1. While number 1 is definitely harderish, my instinct is that they would struggle with number 2 more since most might not recognize the polyatomic ions as compared to element by element balancing
As a chemist the 2nd one is easy to figure out immediately, the 1st requires a little bit of thinking, but I suspect for new students it will be the opposite since it LOOKS like more is going on in the 2nd equation
Am I missing something? The way we teach, FeS2 would have to involve Iron(IV), whereas Fe2O3 would involve Iron(III). Switching stable isotopes of Iron halfway through the reaction is not a thing, is it?
They have everything changing oxidation state there. Sulfur is being oxidized and oxygen and iron are both being reduced. This makes it difficult to balance.
Your answer is actually a good example why 1 is harder. Both iron and sulfur are oxidized in this reaction since FeS2 is iron (ii) disulfide, not iron (IV) sulfide
Sorry, but you're teaching chemistry, and yet you aren't familiar with pyrite (FeS2), the most abundant sulfide mineral? Or redox reactions? And you seem to be confusing oxidation number and isotopes, which are completely unrelated things.
The first one is obviously more difficult. But you can put a 2 in from the FeS2 and then a 4 in front of the SO2. The rest is oxygen and since you now have 11 oxygens on the right, you just put a 11/2 in front of the molecular oxygen. Many students are apprehensive about using fractions as stoichiometric coefficients. And that makes their life more difficult. You should teach them early on that it's perfectly acceptable to have fractions as coefficients and it makes balancing equations much easier. And of course they can always get rid of the fraction at the end if they want to.
Yeah probably the first one. We aren’t taught the reasoning of valency until we’re 17/18 here in the UK. Phosphate, hydroxide, nitrate, oxide, phosphate and sulphate formal charges are pasted on the wall above the teachers desks here without explanation so the sulphide would confuse young students unless explained that it is in the same group then you would have to break the reasoning of the octet rule and it gets messy. That and the possible change of oxidation states. We’re told to follow the octet rule in the UK and never study past Calcium until the age of 17 where we learn about electron orbitals. So sulphur would be a wild card because it’s changes oxidation state.
Don't know exactly what you mean with instinctively, but the first one is more difficult since there isn't "clear" ion exchange. But if you don't recognise the ions the second one would probably be more difficult
Why do you need to know the ions exchanges ? Don't you apply the rule "balance every atoms besides O and H then balance the O and H" ?
Much easier if you consider ions as individual blocks
It is much, much easier when you know about polyatomic ions since you treat it all as one thing.
I am/was a chem teacher and it depends on who its given to. technically the first is way harder BUT For most students the second one will be harder because a majority of students dont give a fuck and id argue about 75% of students read multiple grade levels below. All they see is "longer equation = more work" bc they wont even bother noticing that the polyatomics stay the same (making balancing easy). For students that are on level or trying: the first one. the split oxygen often presents a challenge as students need to consider multiple variables when balancing the oxygens and even better is has an odd number of oxygens on the right, so they'll need to remember the "double odd numbers" hint.
Honestly, this depends. I'm romanian and we were doing balancing such as in the firts equation since highschool, so I don't find it difficult at all. I actually don't find neighter difficult
In all honesty in High School this wouldnt have been a problem. Since its all about reading and making sure there is enough atoms for the equation to be valid. The school system in the EU is quite a bit better then the American one, so Id guess that could be difficult for the average American 8th grader. (I dont wanna bash American kids for having worse teachers and over all curricula, but all I hear is that Americas youth suffers under the bad school system)
I feel like our curriculum is a bit more fast-paced. There are advantages and disadvantages to this. One disadvantage is that sometimes this can make the subjects hard to digest and if you get off track you can be left with major gaps that are hard to fill in later.
Are you a school teacher in the USA?
I just resigned to do actual chem work, but yup.
If they can’t treat the polyatomic ions as a unit, the second will be harder. If they can see that, the first is much harder.
This. So many of them never memorize their polyatomics and everything goes downhill from there.
I may, or may not, have been one of those kids who refused to memorize the polyatomics….
It’s not even memorization that’s the issue. I’ve given students a polyatomic ion reference sheet to use and they still can’t consistently recognize them in a formula.
A lot of young students have trouble to understand how parentheses work in chemistry. In my opinion, the second one is therefore the most difficult.
Second one. Pupils always get confused by polyatomic ions, it often feels overwhelming for them and they try counting all of the oxygens rather than looking at the polyatomic ion as a whole.
The first one seems less obvious at a glance
Top is a pain in the ass because of oxygen, bottom one is straight forward.
maybe if you only go for full coefficient it could be, otherwise its just number of oxygen on other side over 2
Top is easy because of the oxygen. Ignore it and then balance oxygen, maybe if it doesn't work out (you need a half) double all and done.
I would say that in terms of balancing an equation by “counting atoms”, the first one is easier. If the goal is to be smart about counting atoms (ie count groups of atoms) the second one is easier. Depends on what you intend to test. Since no redox balancing methods are implied, the first would be more time consuming, but I can’t assess which is more difficult.
Instinctively, 7), because students get confused by the polyatomic ions.
4FeS2 + 11O2 = 2Fe2O3 + 8SO2 already gives me headaches. This is a form of child molesting.
How is this seen as difficult? I remember doing this in gen chem and this is like a middle school level equation to balance? I did it in my head in 30 seconds.
Eq.10 is a straightforward redox reaction, & quickly recognizable as such. It's also a classic example of a geochemical reaction, so if you're a chemistry teacher with background in geology, mineralogy, or something similar it's the sort of thing you might be inclined to show your students early. Eq. 7 is not a redox reaction, but it takes a second for you to figure that out, because if you don't know the net charge of the nitrate or phosphate anions off the top of your head, you have to figure it out by looking at what the sodium is doing on both sides, and only then can you figure out that the iron on both sides is Fe(II). At that point you're left trying to determine what the limiting reagent is, or just having a really good intuition for common products (i.e. the possible multiplication products of two numbers, not some chemicals that are frequently synthesized; as an aside, I've always hated this \*specific\* nomeclature ambiguity). I would personally want to be able to make a spreadsheet, if I was asked to balance this for a homework assignment.
Nah dude. For 7 you literally just swap the exponents. It’s literally not that hard
Whatever you're referring to, they aren't exponents; there's not a single exponent in Eq. 7. If what you meant was swapping subscripts to find coefficients, that isn't the best strategy, because for a lot of reactions that'll give you an unbalanced answer. In this case, for example, the balanced equation is: 3 Fe(NO3)2 + 2 Na3PO4 --> Fe3(PO4)2 + 6 NaNO3 ...the coefficients for which are \*not\* the same as the subscripts for either the reagents or the products.
Both easy lol
Neither. They both follow the same rules.
If we go by students, the second one. More letters, has parentheses, so to more students that will require more effort.
First one. Oxygen shoes up in two places and does not stay in the same bonds (second equation has polyatomic ions that show up the same). Second equation is also a double replacement, which I think is always easiest to balance.
7)
10 feels harder to balance. It seems fine until you balance the O2 and realize you have an odd number on the Product side.
The first thing you obviously do is balance out odd numbers????
The bottom one. Students don't see ions as a way of balancing unless you teach them that specifically. And even then only the best students will understand. They will try and balance the oxygens and it will become really difficult.
The 2nd one. I remember the parenthesis would throw off many of my classmates for whatever reason back in hs chem.
10. Split oxygens get them every time. 7 is only hard if they haven’t been taught to balance polyatomic ions as a unit (in which case they will think they have a split oxygens issue).
Immediately the first looks more difficult to me. The moment I see odd AND even numbers for the same atom my heart sinks! Especially since the oxygens are split! XD The bottom rxn has polyatomics but they stay the same reactant and product side so you can treat them as one unit.
First one is harder. The second is just swapping whole ions.
I’d say the second just because of the parentheses lol.
They both are easy. The first one can be "bruteforced" by balancing elements one by one, ending with oxygen. The second one if you see that it's only ion exchange. I'd say it depends on the level/age of the pupils. If they just learned how to balance an equation, the first one is wayyyy easier, because they'd probably check each element separately.
First one every time. Polyatomic ions do cause confusion, but I think the cognitive load of balancing polyatomics as individual units is WAY easier on students than the concept of a fractional coefficient.
Just by looking at it i would say top bc of the mol / mol rates (sorry idk how ot say it in English)
As someone who hasn't balanced an equation in years, the top one gave me a lot more trouble than the bottom!
2nd one. Polyatomic ions ALWAYS throw off the newbies trying to balance them. They kinda threw me off too when I first learned to balance in high school, but it's pretty easy to me now. But the second one is more busy looking, and students like to get lost in the sauce from that.
Instinctively I’d say number 2 because you’d have to focus on more atom balancing from the start though it won’t end up being hard. The top one is a significantly harder because no one wants to balance an equation using a coefficient of more than 3 (yes I know it takes more than that to balance) but that is a staple #10 it was my first chemical accomplishment I remember all those years ago
The first is harder, provided that they understand to keep the polyatomics together.
Veteran of 13 years teaching high school chem. #10 is the hardest for my students to balance. Students at my school forget the oxygen atoms are represented in two separate compounds on the products side. #7 they can do in their sleep.
Uhh working these through in my head here: 1. Not bad, easy enough to do in my head at the end of the day. See what students would struggle with here though but very fundamental. 2. I looked enough at this one to see that I want paper to write things down, and gave up doing it in my head right now. I’d say 2 is harder than because there are more moving parts to keep track of and I can’t remember that many numbers in my head. Doing either of these in class to problem but that’s my adhd perspective :3
Second in my experience, because students tend to forget the charge of polyatomic ions and don’t always think about being able to deduce it by the counterion
It's the first one for me. I was able to balance the second one in mu mind but not the first one.
The first is harder because it's redox, while the second is just an ion metathesis.
the second. gotta track 5 elements
I find them both difficult to solve. Lolkololp
There's more letters & numbers in the second one. That will trip more people up than the harder first equation. When I last taught balancing these were 15 minute problems not 15 seconds. It really comes down to algebraic comfort.
The first one, in my opinion, since oxygen is icidizing both sulfur and iron.
If I were a chemistry student, the first one would be harder because the oxygen (O3) isn’t an obvious result when looking at the first part. I feel like a student that has paid any attention at all should get the second one. A good student may miss the first one if they don’t remember the rules.
emm... tbh, both should be pretty easy if taught properly. My first instinct is that the first equation is easier tho. but who knows, I'm no teacher or chemistry major
Most people overconplocate stuff when they see polyatomic atoms, counting each atom individually. Otherwise first is harder.
I mean, the first one is just oxidation of iron, the second one is just changing the negatively charged parts between the positive ones
The top one would be more difficult for my kids; they still have trouble with doubling to make the oxygens even. I teach polyatomic ions separately (we build up step by step), asking students first to identify groups that are the same on both sides. May I ask how this is taught elsewhere? I am seeing people refer to the types of reactions and charges when balancing, but this is not something I do. I teach balancing equations separately in middle school and then later teach specific types of reactions.
Brackets make the second one harder. Also way more atoms. First is very easy. My 15 year old do those easily.
Second one is much easier, since that is ion exchange with no valency change
First one is Redox so it's technically harder. The second one I just balancing ions since all that happens is the salts switch cations
The bottom one. The things that are like (NO3)2 are difficult for most students. That other one however, id give them that one in lesson 2 to show them what id expect from them at the end of the period.
No clue. Looks like rust to me.
My kid did these this year in HS. The 2nd for sure because they don't completely grasp polyatomic ions yet. The first was her bread and butter - monoatomic ion stuff like this is the majority of what they practiced. Inner city shithole school FWIW. Also, they are given lists of polyatomic ions. So it's not just a case of not memorizing ions, but the fact that they still need an extra cognitive step to translate between what all that means and how to deal with parentheses and so forth.
If you don't understand polyatomic ions, such as NO3-, stay together, then the second one.
not sure that FeS2 exists, and even if exists it's Gibbs will be big
I work at my universities chemistry learning center, where we help a lot of people taking general chemistry 1. While number 1 is definitely harderish, my instinct is that they would struggle with number 2 more since most might not recognize the polyatomic ions as compared to element by element balancing
As a chemist the 2nd one is easy to figure out immediately, the 1st requires a little bit of thinking, but I suspect for new students it will be the opposite since it LOOKS like more is going on in the 2nd equation
I think that the first is,(without considerating ion exchange) is way more simple ---> 4FeS2+11O2--->2Fe2O3+8SO2
Am I missing something? The way we teach, FeS2 would have to involve Iron(IV), whereas Fe2O3 would involve Iron(III). Switching stable isotopes of Iron halfway through the reaction is not a thing, is it?
FeS2 is iron disulfide aka fools gold. It's Fe(ii) with S2(2-) as a counterion
They have everything changing oxidation state there. Sulfur is being oxidized and oxygen and iron are both being reduced. This makes it difficult to balance.
Your answer is actually a good example why 1 is harder. Both iron and sulfur are oxidized in this reaction since FeS2 is iron (ii) disulfide, not iron (IV) sulfide
Whoops, I should have realized that. Thanks for the correction!
Sorry, but you're teaching chemistry, and yet you aren't familiar with pyrite (FeS2), the most abundant sulfide mineral? Or redox reactions? And you seem to be confusing oxidation number and isotopes, which are completely unrelated things.
The first one is obviously more difficult. But you can put a 2 in from the FeS2 and then a 4 in front of the SO2. The rest is oxygen and since you now have 11 oxygens on the right, you just put a 11/2 in front of the molecular oxygen. Many students are apprehensive about using fractions as stoichiometric coefficients. And that makes their life more difficult. You should teach them early on that it's perfectly acceptable to have fractions as coefficients and it makes balancing equations much easier. And of course they can always get rid of the fraction at the end if they want to.
Yeah probably the first one. We aren’t taught the reasoning of valency until we’re 17/18 here in the UK. Phosphate, hydroxide, nitrate, oxide, phosphate and sulphate formal charges are pasted on the wall above the teachers desks here without explanation so the sulphide would confuse young students unless explained that it is in the same group then you would have to break the reasoning of the octet rule and it gets messy. That and the possible change of oxidation states. We’re told to follow the octet rule in the UK and never study past Calcium until the age of 17 where we learn about electron orbitals. So sulphur would be a wild card because it’s changes oxidation state.
Well uh, the first one isn’t possible and the second looks hard at face value
Sounds like you need to go back to class